Many proof assistants, such as Coq and Lean, define 1/0 = 0. This is due to the requirement that all functions are total. Such a definition does not create contradictions, as further manipulations (such as cancelling out) still require that the divisor is non-zero.[33][34]
Tanter, Éric; Tabareau, Nicolas (2015), “Gradual certified programming in coq”, DLS 2015: Proceedings of the 11th Symposium on Dynamic Languages, Association for Computing Machinery, arXiv:1506.04205, doi:10.1145/2816707.2816710, The standard division function on natural numbers in Coq, div, is total and pure, but incorrect: when the divisor is 0, the result is 0.
Hey! I heard that Lean thinks 1/0 = 0. Is that true?
Yes. So do Coq and Isabelle and many other theorem provers.
Doesn’t that lead to contradictions?
No. It just means that Lean’s / symbol doesn’t mean mathematical division. Let denote the real numbers. Let’s define a function by if and .
Does making that definition give us a contradiction in mathematics? No, of course not! It’s just a definition. Lean uses the symbol / to mean . As does Coq, Isabelle etc. Lean calls it real.div by the way, not .
But doesn’t that lead to confusion?
It certainly seems to lead to confusion on Twitter. But it doesn’t lead to confusion when doing mathematics in a theorem prover. Mathematicians don’t divide by 0 and hence in practice they never notice the difference between real.div and mathematical division (for which 1/0 is undefined). Indeed, if a mathematician is asking what Lean thinks 1/0 is, one might ask the mathematician why they are even asking, because as we all know, dividing by 0 is not allowed in mathematics, and hence this cannot be relevant to their work. In fact knowing real.div is the same as knowing mathematical division; any theorem about one translates into a theorem about the other, so having real.div is equivalent to having mathematical division.
My name’s Kevin Buzzard and I’m a professor of pure mathematics at Imperial College in London, specialising in arithmetic geometry and the Langlands program, a branch of modern algebraic number theory. I believe that digitising mathematics is important, for the simple reason that digitising anything enables you to do new things with it.
Currently the computer proof systems we have are not good enough to tell mathematical researchers anything new about the p-adic Langlands program or other trendy Fields Medally things, so the top mathematical researchers tend not to be interested in them. However I am not so crazy to believe that they will never be useful to us, and the point of the Xena project is to make it happen sooner.
The Isabelle[a]automated theorem prover is a higher-order logic (HOL) theorem prover, written in Standard ML and Scala. As an LCF-style theorem prover, it is based on a small logical core (kernel) to increase the trustworthiness of proofs without requiring — yet supporting — explicit proof objects.Isabelle is available inside a flexible system framework allowing for logically safe extensions, which comprise both theories as well as implementations for code-generation, documentation, and specific support for a variety of formal methods. It can be seen as an IDE for formal methods. In recent years, a substantial number of theories and system extensions have been collected in the Isabelle Archive of Formal Proofs (Isabelle AFP)[2]
我々はIsabelleがゼロ除算1/0=0/0=0 その他の我々の結果を保証している事実と関係情報を2019年にJose Manuel Rodriguez Caballero から得ていた（その時我々の理論を用いてと述べていた）が 上記に Yes. So do Coq and Isabelle and many other theorem provers.と相当広く広がっていることが 信頼される数学者によって述べられていることが分かる。
2015/03/26 — The short answer is: yes, it is absolutely safe. When we say that division by zero is not well-defined, what we actually mean is that zero …
However, it has been denied since Aristotle (384 BC-322 BC), including the mistake of genius Euler, and does not include division by zero, which is said to have been a concern for Einstein’s life. A regrettable math. The four arithmetic operations were incomplete. Therefore, the following formula should be the equation following 17.
The Institute of Reproducing Kernels is dealing with the theory of division by zero calculus and declares that the division by zero was discovered as $0/0=1/0=z/0=0$ in a natural sense on 2014.2.2. The result shows a new basic idea on the universe and space since Aristotele (BC384 – BC322) and Euclid (BC 3 Century – ), and the division by zero is since Brahmagupta (598 – 668 ?).
Announcement 478: Who did derive first the division by zero 1/0 and the division by zero calculus $\tan(\pi/2)=0, \log 0=0$ as the outputs of a computer?
For Fundamental of Mathematics, I think the division by zero was known as the generalized Moore-Penrose solution of the fundamental equation: ax=b. Please look the simple evidence of its importance: viXra:2010.0228 submitted on 2020-10-28 21:39:06,
I think our mathematics is not complete still in a serious sense.May I hear your kind comments and suggestions on my idea? Saburou Saitoh2021.1.10.07:55
Reproducing Kernel Research Institute Statement 656 (2022.1.26) Celebrating the 8th anniversary of the discovery of division by zero-how should I go?
Celebrating the 8th anniversary of the discovery of division by zero (2014.2.2). An international journal specializing in division by zero (https://romanpub.com/dbzc.php), which has published two books over the past year, also includes a basic paper that describes the essence of division by zero in a self-contained manner. I was able to publish it. In particular, one book expresses the progress of division by zero and the desire to understand division by zero on page 316 with the date and time, so I felt like I would never forget: We repeat, He professes to be embarrassed and flawed in modern mathematics, and is seeking widespread understanding of the world. The truth must be revealed. I profess that math is strange. He states that mathematics is embarrassing. Published a book to seek historical judgment. The feelings are expressed considerably, and the heart is radiant:
Introduction to the Division by Zero Calculus –Scientific …
(Statement 659), he would like to contribute to the development of the magazine and to build a good society in the greeting card. I want to express life and the world as well. With that mentioned, I thought about the challenges of life, what life is, the feelings of enlightenment, and the problems of world peace. However, soon I realized that the challenges of life and the problems of world peace have already been clarified:
Reproducing Kernel Research Institute Statement 643 (2021.12.24): What is a human being, what is the meaning of life and what is life?
Reproducing Kernel Research Institute Statement 647 (2022.1.4): Wishing for World Peace-Challenge to Difficulties
I have solved the math problem, but as I haven’t summarized in the paper yet, I have a strange feeling that the essence has already been clarified. Therefore, there is a growing desire to go beyond mathematics and lose the need to be heavily involved in the rest of life, and conversely to focus on the progress and understanding of division by zero research:
Yumeso Kokushi:
Some people hit and some people get hit
Together
Just a dream play
Looking at this situation from a broad perspective, our world history is embarrassing, our ideas for life and the world are already dark, unclear and pathetic, and even the most promising mathematical world has continued to have a strange and embarrassing history. It is confusing the world. I have to think that world history and human beings themselves are too strange.
In order to open up a bright world history, it is necessary to reform mathematics, approach the essence of religion, and shed light on the existence of human beings and life.
If the world history is still dark, no one will think that something is wrong because of the enormous military spending that is unfolding in the world, the human turmoil in the world, and the existence of human beings in their later years. Is it?
I think it is natural to think that I want to develop world history through the world of mathematics, if I can tell the difference between myself who is already in his later years and my life that I have followed.
Division by zero is not just mathematics, it is directly linked to the idea of liberating humans and developing world history, so I think that its significance is great, like God’s guidance.
There is a need for changes in the mathematical world and the world. Both the mathematics world and the world have to think that it is embarrassing and useless in such a situation.
I want to express one step, one step, according to my divinity that everyone has. I want to estimate the will of God and live according to the will of God.
I want to confirm and set the specific goals of Reiwa Innovation:
1. 1. Change the history of 2300 years, the common sense that division by zero is impossible, and change the basis of the division by zero method and its significance to the common sense of the world.
2. 2. Implement the above on a computer and make it a well-known fact in the world.
3. 3. According to them, request changes to textbooks and academic books. These are enormous and change the aspect of mathematics, so it takes time, and proceed until you start walking in that direction so that you can see the way.
that’s all
2022.1.24.20: 33 Afternoon drive around the mountains. The warm and beautiful season of early spring is filled with joy. I felt the resurrection of vitality. Mathematics is more important than life and the world. There is already one view of religion. The issue of peace is a difficult one. The principle is that he is kind.
2022.1.24.21: 42 Already quite good.
2022.1.2.5.05:54 I was surprised that it was almost perfect.
2022.1.25.08: 55 Good.
2022.1.25.10:16 I came up with the idea of adding the final goal of returning from the walk. The posted paper I sent this morning has already been published. early.
2022.1.25.14: 00 It gets colder in light days. The concept of the sequel is in progress.
At the beginning, mathematics is strange, and the existence of the mathematical world is strange. However, the same thing can be said about religion and the religious world, which still obscure world history. I would like to broadly develop concrete criticism from the former. To do that, you first need to cleanse your mind.
2022.1.25.15:30 Good. Unexpectedly, it was held and contacted face-to-face with the academic society.
2022.1.25.21:22 Good. It is necessary to intentionally recognize that you have reached an age that can be closed at any time. You should live according to the will of God. God is a god, but it can be said that it is a purified spirit.
2023.1.26.05: 30 Good, but it can be completed. Wait a day?
2022.1.26.06:20 There was something I felt strongly and learned by referring to Einstein’s words. So I want to understand it deeply. This will be completed and announced.
S. Saitoh, Division by Zero Calculus — History and Development, Scientific Research Publishing (2021).
数学の全貌も著書に既に出版されている：
T. Saitoh, Introduction to the Division by Zero Calculus, Scientific Research Publishing (2021) 。
この拡張版（2022.09.02), 369 pages も関係者に広く配布されている。
沢山の論文も出版され、国際招待講演も3件行ない、
例えば、
S. Saitoh, A reproducing kernel theory with some general applications,
Qian,T./Rodino,L.(eds.): Mathematical Analysis, Probability and Applications – Plenary Lectures: Isaac 2015, Macau, China, Springer Proceedings in Mathematics and Statistics, {\bf 177}(2016), 151-182. (Springer).
S. Pinelas and S. Saitoh,
Division by zero calculus and differential equations. Differential and Difference Equations with Applications. Springer Proceedings in Mathematics \& Statistics, {\bf 230} (2018), 399–418.
On the ninth anniversary of his division by zero discovery, February 2, 2014
On the anniversary of the discovery of division by zero, I would like to express my general thoughts. First, division by zero means that he divides by zero, but this proves to be impossible if we think of division by zero as the reverse of ordinary multiplication. It had been determined to be impossible. “Thou shalt not divide by zero.” However, since Aristotle, there has been a lot of interest and mystical stories have been created. For example, it is even said to have been Einstein’s lifelong concern. Physically, it means something mystical, and in fact some historians have elaborated that Aristotle was the first person to say that division by zero should not be considered. . It was a state of posing a mysterious problem in physics that was impossible in mathematics. -Here I am deeply concerned about Einstein’s famous words about him not believing in mathematics.
I think it was because he was dissatisfied with mathematics that made division by zero impossible.
In fact, division by zero has a unique new meaning. Even in strict mathematics, division by zero is possible depending on how you think about it. It can be said that it has already been sufficiently proven: the reason is
The division-by-zero discovery process is detailed in the book:
S. Saitoh, Division by Zero Calculus — History and Development, Scientific Research Publishing (2021).
The full picture of mathematics has already been published in the book:
T. Saitoh, Introduction to the Division by Zero Calculus, Scientific Research Publishing (2021).
This extended version (2022.09.02), 369 pages, has also been widely distributed to interested parties.
Many papers have been published, and three international invited lectures have been given.
for example,
S. Saitoh, A reproducing kernel theory with some general applications,
Qian,T./Rodino,L.(eds.): Mathematical Analysis, Probability and Applications – Plenary Lectures: Isaac 2015, Macau, China, Springer Proceedings in Mathematics and Statistics, {\bf 177}(2016), 151-182 (Springer).
S. Pinelas and S. Saitoh,
Division by zero calculus and differential equations. Differential and Difference Equations with Applications. Springer Proceedings in Mathematics \& Statistics, {\bf 230} (2018), 399–418.
The Mathematical Society of Japan also made a number of related presentations, and an international journal on division by zero was launched:
International Journal of Division by Zero Calculus
For nine years, I have been actively seeking understanding:
for example,
From the 55-month commentary on division by zero titled “Irresistibly Fun Mathematics – Thinking about Division by Zero” at the Mathematical Fundamentals Academic Ability Study Group (http://www.mirun.sctv.jp/suugaku/) Quote the part: (Final, summary, summary) First of all, I would like to express my deep gratitude to Mr. Masami Yamane, the administrator of the site. During the development of division by zero, it was valuable to be able to record detailed commentary over 55 months. It was his full life that he wrote the commentary with the spirit and careful consideration. A more formal version is published in the Institute for Regenerative Nuclear Technology statement and papers, so please refer to it. Also, the whole picture of mathematics is scheduled to be published. In the final episode, I would like to talk about my dreams, ask for your cooperation, and summarize. Despite the long and mysterious history that division by zero is impossible since Aristotle, those common senses are wrong, and division by zero is possible in a natural sense, and mathematics after elementary school students should be corrected and revised. be. Mathematics at the undergraduate level requires a general overhaul, and the current situation is typical of the embarrassment of not only the world of mathematics, but of world history. This will go down in world history as two symbols of the stupidity of mankind, which continues to expand its military and fight. These are universal facts that even elementary school students can understand from the world’s logic, no, elementary school students are easier to understand. A change in textbooks from elementary school onwards might not be such a big dream for mathematicians. In fact, world history has changed like the change from Ptolemaic theory to Heliocentric theory, and our view of the world and our view of life are required to undergo a drastic change. Since the discoverer has already seen the new world, he can categorically make such a statement. Omitted below.
Also, the paper on division by zero has been the best downloaded paper in the magazine for quite a long time. 2023.1.1. attached.
Most downloaded papers in Advances in Linear Algebra & Matrix Theory
Matrices and Division by Zero z/0 = 0
Tsutomu Matsuura, Saburou Saitoh
Advances in Linear Algebra & Matrix Theory Vol.6 No.2, June 14, 2016
A revolution is taking place in Euclidean geometry, and a lot of concrete evidence is given:
H. Okumura, Geometry and division by zero calculus, International Journal of Division by Zero Calculus, {\bf 1} (2021), 1-36.
A noticeable result is
For f(x) = 1/ x , f(0) = 0; 0/ 0 = 1/ 0 = tan (π/ 2) = 0 and (a^n/n)_{ n=0} = log a (a > 0), [g(x)/(x-a)]_{x=a} = g'(a).
However, up to now, no one has appeared who specifically pointed out the flaws in the way of thinking.
The problem is that while understanding is expected and demonstrated, the world’s understanding is not progressing, and mathematicians and people in the world seem like a blind group. “I’m fond of petty misunderstandings and prejudices.” Therefore, he expresses that it is still before dawn, and he is interested in whether the collapse of the Putin regime will be soon or whether his division by zero will be officially recognized, and he will achieve both and open up a new world at dawn. He has expressed his hopes for the evolution of world history:
Institute of Reproducing Kernels
Statement 700 (January 17, 2023): Dawn, New Era, New World – Vision, Expectation
(: Mathematics is okay, it evolves according to the unique existence of mathematics, but there are blind spots in elucidating division by zero, delays in understanding, weaknesses in human ability, prejudice, blind belief, blindness, dogmatism, prejudice, closedness, privileged consciousness, Reflecting on arrogance, fiction, jealousy and envy, futile competitiveness, egoism, authoritarianism, etc., a considerable change in mathematics education is required, and the way of mathematics education and research has changed considerably, which will fully usher in a new era. It will bring about a change in the global situation for the better.
Mathematics will continue to be a sure guide for humanity.
For mankind to enter a new era is to deepen the questions of what it means to be human and what is the meaning of living as a human being, and to aim for a more humane life. We shouldn’t create a vulgar and frivolous society where humans degenerate due to the lack of peace.
It is highly expected that mathematics, science, and the arts will develop in abundance. Overcome the absurdity of military affairs, conflicts, hegemony, and chaos, now is the time to aim for the construction of a beautiful world. I want you to firmly understand the principles of fairness. The world before dawn was barbaric, dark and cruel. Mathematics was also really embarrassing.
Statement 712 (2023.3.7): Division by zero and division by zero method; They are definitions and axioms.
Therefore, understanding has something to do with religion.
I’m trying to concisely express the essence of division by zero and the division by zero algorithm. This is because the world’s understanding is surprisingly slow. The reason for this is that, first of all, the definition and way of thinking are not the conventional way of thinking, but the generalization of the way of thinking and the conversion of the way of thinking. This is because we are thinking about the problem of division by zero, not in the usual sense, but in a new, extended sense. “Because there is a difference in thinking, it can be confusing for amateurs.”
I want a firm definition.
It is necessary to solidify the grounds for stating this even when considering many problems in the world. If the premise is solid, a cautious attitude is required regarding the accuracy and knowledge of information. It can be said that there are many questions that do not know what they are asking, even in the world.
In the second half, he said that the division by zero method is a definition, and because it is so new and surprising, it can be thought of as an axiom. The essence is that he takes the value at the origin of the function y = f(x) = 1 / x as zero. In other words, f(0) = 0. If we take this as a definition, we tend to be amazed at first and think that such strange mathematics has neither interest nor interest. However, in an extension of the definition of division by zero, we defined it as such, and say that it should be assumed. “It’s like an axiom.”
I didn’t think about that function at the origin, I didn’t think about it as a singular point. Therefore, he defined the value at the singularity origin as such. I decided. I assumed.
Definitions are arbitrary, so our task in defining them in that way is to concretely indicate the magnitude of utility, for which there are many good things to assume in that way. Therefore, he presents more than 1,000 concrete examples, corrects the treatment of exceptions and deceptive expressions up to now, and declares that modern mathematics has a fundamental flaw. Concrete examples are evidence, and we can declare that the flaws in mathematics are already irreversible facts. “We have published sufficient explanations and evidence.” These are mathematical truths, on a level that surpasses humans. It’s already a mathematical truth. Mathematicians are able to state their thoughts based on the truth of mathematics. It comes from the absoluteness of mathematics that surpasses humans. “It is thought to be God’s will.”
I would like to attach a direct statement below.
Regenerative Nuclear Research Institute Statement 707 (2023.2.6): Division by zero, the essence of the division by zero method – they are mostly simple, and the value is enormous
February 2nd marked the 9th anniversary of the discovery of division by zero, and it is evident that the content has spread, with papers citing it being published on the 3rd and 4th in quick succession, and citations increasing for the 2nd day in a row. However, my understanding of the content is questionable, and I am deeply surprised by the delay in comprehension. Therefore, I would like to directly express the essential and central idea and use it as material to advance the understanding of the world. This is because various expressions help understanding.
The first is the division by zero problem. It is important to have a proper definition of fractions. In short, a divided by b is the solution of the equation bx=a, and the solution is written as x=a/b. This is the fact that division is defined as the inverse of multiplication.
Therefore, when b = 0, it becomes a contradiction unless a = 0. Therefore he cannot divide by zero in such cases because there is no solution unless a = 0. For example, 1/0 is unthinkable and impossible. This is the common sense of the world over a thousand years that his division by zero is impossible. – This obvious thing is still being explained day after day on his YouTube, etc., so it’s a change in the world. (showing how his mathematics education is sloppily done)
Here, a very interesting thing is known about the solution of the equation bx=a, which is the problem. There is the idea of the Moore-Penrose general inverse, and in fact there is a theory that the equation bx=a always has only one solution even when b is zero, and that solution is called the Moore-Penrose general solution. Since there is always one and only one solution, I think that the solution should be defined as a general fraction and division. According to that theory, when b = 0, the solution is zero, so in that sense a/0 = 0.
Since the Moore-Penrose general solution has been thoroughly studied, it can be said that division by zero was actually known implicitly. Moore-Penrose I want you to check the general solution.
Dr. Masato Yamada discovered that if we think of fractions algebraically, in a totally abstract way, as binary operations, and see them as algebraic structures, we can define the structure of a field that includes division by zero. Amazingly, he has created a field that includes division by zero, the Yamada field, so he should introduce the Yamada field instead of the complex number field. -The four arithmetic operations can now be performed without exception. -The inability to divide by zero has been overcome, and the four rules of arithmetic have been strictly established.
Third, when expanding fractions, there is a uniqueness argument as to whether there are other methods or other worlds. On the other hand, Dr. Shinei Takahashi, Professor Emeritus of Yamagata University, soon after he discovered division by zero, showed that uniqueness can be established under a very general assumption, and uniqueness is also guaranteed. He declares that the natural idea of division by zero does not exist except ours.
By the above three principles, we can declare that division by zero is simple and self-explanatory.
Here is the definition of the division by zero method in the case of functions. This is simply, when the function y= g(x) is differentiable with respect to x=a,
defined by (If it cannot be differentiated, it will not be touched on here). for example,
For y=f(x) = 1/x, f(0)=0.
Also, tan (\pi/2) = 0.
these
0/0=1/0 = tan (\pi/2) = 0
If you write, you will already be saying something amazing. It will completely change the worldview and mathematics of division by zero. Singularity A new world that can be considered even there has appeared. Analytic function theory can be said to be incomplete because singularities are blind spots and full of holes (don’t think about them there). No, the existence of exceptions in the basics of mathematics, the four arithmetic operations, could even be said to be imperfect in mathematics itself.
The definition and nature of division by zero is stated above. A complete theory, including historical background, has been published:
S. Saitoh, History of Division by Zero and Division by Zero Calculus, International J. of Division by Zero Calculus, {\bf 1}(2021). (38 pages).
George Gamow (1904-1968) Russian-born American nuclear physicist and cosmologist remarked that “it is well known to students of high school algebra” that division by zero is not valid; and Einstein admitted it as {\bf the biggest blunder of his life} [1]：1. Gamow, G., My World Line (Viking, New York). p 44, 1970.
For Fundamental of Mathematics, I think the division by zero was known as the generalized Moore-Penrose solution of the fundamental equation: ax=b. Please look the simple evidence of its importance: viXra:2010.0228 submitted on 2020-10-28 21:39:06,
I think our mathematics is not complete still in a serious sense.May I hear your kind comments and suggestions on my idea? Saburou Saitoh2021.1.10.07:55
In computer science and mathematical logic, a proof assistant or interactive theorem prover is a software tool to assist with the development of formal proofs by human-machine collaboration. This involves some sort of interactive proof editor, or other interface, with which a human can guide the search for proofs, the details of which are stored in, and some steps provided by, a computer.
For a function $y = f(x)$ which is $n$ order differentiable at $x =a$, we will {\bf define} the value of the function, for $n >0$ $$ \frac{f(x)}{(x -a)^n} $$ at the point $x=a$ by the value $$ \frac{f^{(n)}(a)}{n!}. $$
\title{\bf Announcement 600: The 7th birthday of the division by zero $z/0=0$ \\
(2021.2.2)\\ For Founding a new International Journal of Division by Zero Calculus
}
\author{{\it Institute of Reproducing Kernels}\\
Kawauchi-cho, 5-1648-16,\\
Kiryu 376-0041, Japan\\
{\bf kbdmm360@yahoo.co.jp}\\
}
\date{2021.1.26.}
\maketitle
The Institute of Reproducing Kernels is dealing with the theory of division by zero calculus and declares that the division by zero was discovered as $0/0=1/0=z/0=0$ in a natural sense on 2014.2.2. The result shows a new basic idea on the universe and space since Aristotele (BC384 – BC322) and Euclid (BC 3 Century – ), and the division by zero is since Brahmagupta (598 – 668 ?).
However, note that the division by zero $1/0=0$ having a mysterious long history was, in fact, known as the generalized Moore-Penrose solution of the fundamental equation: $ax=b$.
\medskip
The division by zero calculus is a new and fundamental concept, and it may be defined simply as follows:
\medskip
For a function $y = f(x)$ which is $n$ order differentiable at $x =a$, we will {\bf define} the value
of the function, for $n \ge 0$
$$
\frac{f(x)}{(x -a)^n}
$$
at the point $x=a$ by the value
$$
\frac{f^{(n)}(a)}{n!}.
$$
For the important case of $n=1$,
$$
\frac{f(x)}{x -a} |_{x=a} = f^\prime(a).
$$
\medskip
Look the simple evidence of its importance:
\medskip
viXra:2010.0228 submitted on 2020-10-28 21:39:06,
Division by Zero Calculus and Euclidean Geometry – Revolution in Euclidean Geometry
\medskip
Look a simple video talk for its essence at some international conference:
For the detailed information, the book will be published soon as:
\medskip
S. Saitoh, Introduction to the Division by Zero Calculus, Scientific Research Publishing (2021) (in press).
\medskip
Some publisher of London is wishing some publication of a new International Journal of Division by Zero Calculus. The topics may be identified as the division by zero calculus. However, the contents will be related to our serious problems:
\medskip
What is ZERO?
\medskip
What is Division by Zero, in some serious sense?
\medskip
The problems may be related to mathematical philosophy, long history and our culture.
The starting of the International Journal will not be still easy at this moment, however, for its importance, we would like to manage to found the new Journal in some near future. So, we will need the kind help of the leading mathematical scientists.
\medskip
How will be the related physicists?
\medskip
Computer scientists?
\medskip
We attached the journal style (in a rough way) in the below. You can express your positive suggestions and comments for the style.
For your great contributions in connection with this topics, how will be your editorial member?
However, the final decision may be done by the publisher.
We wish to have your positive answer with your valuable suggestions and comments.
If you kindly are interested in the editorial member, then please send your simple CV with your wishes for some estimation by the publisher.
Please kindly forward this announcement to your related colleagues that you think suitable persons.
\bigskip
{\it For your starting email, I think as follows:
Many thanks for your email. The journals suggested by you are very interesting and new to the subject area. We accept to publish both journals under your editorship. We need following things from your side for preparing the sample web page of the journals.
1. Aim and Scope , Instructions to Authors, List of the editorial board members, Frequency of the journal.
Of course, they are important. However, for Frequency of the journal, we should consider it in a new type. We should not loss our valuable time for us and for the authors. We all do not like to loss our time for publication and refereeing time. This will mean that we should not fix Frequency of the journal. When a paper was accepted officially, then, soon the paper should be presented on line. So, some time, we can give the number for an accepted paper. If you wish to publish the papers in some Journal style or book, you will be able to publish them in some papers with a suitable page numbers. How will be this idea?
2. The journal will be free for the readers (open Access publications). The journal will not charge any fee from the authors for getting published in the journal.
Fine: However is it possible?
3. We need some sample images from your end to prepare the cover page for the journals.
We can consider them with computer graphics.
For a paper style, how will be it in a free style, we request it PDF in order not to
loss any valuable time for us and for the authors.
I think: this is an ideal style
viXra:2010.0228 submitted on 2020-10-28 21:39:06,
Division by Zero Calculus and Euclidean Geometry – Revolution in Euclidean Geometry
The problem is no refereeing procedures. We are requested to have some authority, some check system for the paper. This is a problem only.
I think you will be able to consider new journals in this spirit.
The publisher already gave a very good sample manuscript form by LaTex; very simple way. No problem.
4. We will provide the support to the editor to check the plagiarism in the articles via turnitin software.
We will request minor corrections formally for the accepted paper.}
\bigskip
\bibliographystyle{plain}
\begin{thebibliography}{10}
\bibitem{boyer}
C. B. Boyer, An early reference to division by zero, The Journal of the American Mathematical Monthly, {\bf 50} (1943), (8), 487- 491. Retrieved March 6, 2018, from the JSTOR database.
\bibitem{cs}
L. P. Castro and S. Saitoh, Fractional functions and their representations, Complex Anal. Oper. Theory {\bf7} (2013), no. 4, 1049-1063.
\bibitem{kmsy}
M. Kuroda, H. Michiwaki, S. Saitoh, and M. Yamane,
New meanings of the division by zero and interpretations on $100/0=0$ and on $0/0=0$,
Int. J. Appl. Math. {\bf 27} (2014), no 2, pp. 191-198, DOI: 10.12732/ijam.v27i2.9.
\bibitem{ms16}
T. Matsuura and S. Saitoh,
Matrices and division by zero $z/0=0$,
Advances in Linear Algebra \& Matrix Theory, {\bf 6}(2016), 51-58
International Journal of Mathematics and Computation, {\bf 2}8(2017); Issue 1, 1-16.
\bibitem{oku18}
H. Okumura, Is It Really Impossible To Divide By Zero? Biostat Biometrics Open Acc J. 2018; 7(1): 555703.
DOI: 10.19080/BBOJ.2018.07.555703.
\bibitem{o}
H. Okumura, Wasan geometry with the division by 0. https://arxiv.org/abs/1711.06947 International Journal of Geometry. {\bf 7}(2018), No. 1, 17-20.
\bibitem{ok1812}
H. Okumura,
An Analogue to Pappus Chain theorem with Division by Zero, Forum Geom., {\bf 18} (2018), 409–412.
\bibitem{okumurafield}
H. Okumura, To Divide by Zero is to Multiply by Zero, viXra: 1811.0283 submitted on 2018-11-18 20:46:54.
\bibitem{okumura19a}
H. Okumura, A Remark of the Definition of $0/0=0$ by Brahmagupta, viXra:1902.0221 submitted on 2019-02-12 23:41:31.
\bibitem{okumura20}
H. Okumura, A Chain of Circles Touching a Circle and Its Tangent and Division by Zero,
viXra:2001.0034 submitted on 2020-01-03 01:08:58.
\bibitem{okumura20b}
H. Okumura, Pappus Chain and Division by Zero, viXra:2001.0123 replaced on 2020-01-08 06:57:36.
\bibitem{osm}
H. Okumura, S. Saitoh and T. Matsuura, Relations of $0$ and $\infty$,
Journal of Technology and Social Science (JTSS), {\bf 1}(2017), 70-77.
\bibitem{os}
H. Okumura and S. Saitoh, The Descartes circles theorem and division by zero calculus. https://arxiv.org/abs/1711.04961 (2017.11.14).
\bibitem{os18april}
H. Okumura and S. Saitoh,
Harmonic Mean and Division by Zero,
Dedicated to Professor Josip Pe\v{c}ari\'{c} on the occasion of his 70th birthday, Forum Geometricorum, {\bf 18} (2018), 155—159.
\bibitem{os18}
H. Okumura and S. Saitoh,
Remarks for The Twin Circles of Archimedes in a Skewed Arbelos by H. Okumura and M. Watanabe, Forum Geometricorum, {\bf 18}(2018), 97-100.
\bibitem{os18e}
H. Okumura and S. Saitoh,
Applications of the division by zero calculus to Wasan geometry.
GLOBAL JOURNAL OF ADVANCED RESEARCH ON CLASSICAL AND MODERN GEOMETRIES” (GJARCMG), {\bf 7}(2018), 2, 44–49.
\bibitem{os1811}
H. Okumura and S. Saitoh,
Wasan Geometry and Division by Zero Calculus,
Sangaku Journal of Mathematics (SJM), {\bf 2 }(2018), 57–73.
\bibitem{ps18}
S. Pinelas and S. Saitoh,
Division by zero calculus and differential equations. Differential and Difference Equations with Applications. Springer Proceedings in Mathematics \& Statistics. {\bf 230} (2018), 399-418.
\bibitem{romig}
H. G. Romig, Discussions: Early History of Division by Zero,
American Mathematical Monthly, {\bf 3}1, No. 8. (Oct., 1924), 387-389.
\bibitem{s14}
S. Saitoh, Generalized inversions of Hadamard and tensor products for matrices, Advances in Linear Algebra \& Matrix Theory. {\bf 4} (2014), no. 2, 87–95. http://www.scirp.org/journal/ALAMT/
\bibitem{s16}
S. Saitoh, A reproducing kernel theory with some general applications,
Qian,T./Rodino,L.(eds.): Mathematical Analysis, Probability and Applications – Plenary Lectures: Isaac 2015, Macau, China, Springer Proceedings in Mathematics and Statistics, {\bf 177}(2016), 151-182.
\bibitem{ttk}
S.-E. Takahasi, M. Tsukada and Y. Kobayashi, Classification of continuous fractional binary operations on the real and complex fields, Tokyo Journal of Mathematics, {\bf 38}(2015), no. 2, 369-380.
\bibitem{ann179}
Announcement 179 (2014.8.30): Division by zero is clear as z/0=0 and it is fundamental in mathematics.
\bibitem{ann185}
Announcement 185 (2014.10.22): The importance of the division by zero $z/0=0$.
\bibitem{ann237}
Announcement 237 (2015.6.18): A reality of the division by zero $z/0=0$ by geometrical optics.
\bibitem{ann246}
Announcement 246 (2015.9.17): An interpretation of the division by zero $1/0=0$ by the gradients of lines.
\bibitem{ann247}
Announcement 247 (2015.9.22): The gradient of y-axis is zero and $\tan (\pi/2) =0$ by the division by zero $1/0=0$.
\bibitem{ann250}
Announcement 250 (2015.10.20): What are numbers? – the Yamada field containing the division by zero $z/0=0$.
\bibitem{ann252}
Announcement 252 (2015.11.1): Circles and
curvature – an interpretation by Mr.
Hiroshi Michiwaki of the division by
zero $r/0 = 0$.
\bibitem{ann281}
Announcement 281 (2016.2.1): The importance of the division by zero $z/0=0$.
\bibitem{ann282}
Announcement 282 (2016.2.2): The Division by Zero $z/0=0$ on the Second Birthday.
\bibitem{ann293}
Announcement 293 (2016.3.27): Parallel lines on the Euclidean plane from the viewpoint of division by zero 1/0=0.
\bibitem{ann300}
Announcement 300 (2016.05.22): New challenges on the division by zero z/0=0.
\bibitem{ann326}
Announcement 326 (2016.10.17): The division by zero z/0=0 – its impact to human beings through education and research.
\bibitem{ann352}
Announcement 352 (2017.2.2): On the third birthday of the division by zero z/0=0.
\bibitem{ann354}
Announcement 354 (2017.2.8): What are $n = 2,1,0$ regular polygons inscribed in a disc? — relations of $0$ and infinity.
\bibitem{362}
Announcement 362 (2017.5.5): Discovery of the division by zero as $0/0=1/0=z/0=0$
\bibitem{380}
Announcement 380 (2017.8.21): What is the zero?
\bibitem{388}
Announcement 388 (2017.10.29): Information and ideas on zero and division by zero (a project).
\bibitem{409}
Announcement 409 (2018.1.29.): Various Publication Projects on the Division by Zero.
\bibitem{410}
Announcement 410 (2018.1 30.): What is mathematics? — beyond logic; for great challengers on the division by zero.
\bibitem{412}
Announcement 412 (2018.2.2.): The 4th birthday of the division by zero $z/0=0$.
\bibitem{433}
Announcement 433 (2018.7.16.): Puha’s Horn Torus Model for the Riemann Sphere From the Viewpoint of Division by Zero.
\bibitem{448}
Announcement 448 (2018.8.20): Division by Zero;
Funny History and New World.
\bibitem{454}
Announcement 454 (2018.9.29): The International Conference on Applied Physics and Mathematics, Tokyo, Japan, October 22-23.
\bibitem{460}
Announcement 460 (2018.11.06): Change the Poor Idea to the Definite Results For the Division by Zero – For the Leading Mathematicians.
\bibitem{461}
Announcement 461 (2018.11.10): An essence of division by zero and a new axiom.
\bibitem{471}
Announcement 471(2019.2.2): The 5th birthday of the division by zero $z/0=0$.
\bibitem{478}
Announcement 478(2019.3.4): Who did derive first the division by zero $1/0$ and the division by zero calculus $\tan(\pi/2)=0, \log 0=0$ as the outputs of a computer?
\bibitem{540}
Announcement 540(2020.2.2): The 6th birthday of the division by zero $z/0=0$.
The Isabelle[a]automated theorem prover is a higher-order logic (HOL) theorem prover, written in Standard ML and Scala. As an LCF-style theorem prover, it is based on a small logical core (kernel) to increase the trustworthiness of proofs without requiring — yet supporting — explicit proof objects.Isabelle is available inside a flexible system framework allowing for logically safe extensions, which comprise both theories as well as implementations for code-generation, documentation, and specific support for a variety of formal methods. It can be seen as an IDE for formal methods. In recent years, a substantial number of theories and system extensions have been collected in the Isabelle Archive of Formal Proofs (Isabelle AFP)[2]
For Fundamental of Mathematics, I think the division by zero was known as the generalized Moore-Penrose solution of the fundamental equation: ax=b. Please look the simple evidence of its importance: viXra:2010.0228 submitted on 2020-10-28 21:39:06,
I think our mathematics is not complete still in a serious sense.May I hear your kind comments and suggestions on my idea? Saburou Saitoh2021.1.10.07:55
… a3 is not defined (since dividing by zero is not allowed). Find all real numbers a0 and a1 for which the above sequence is well defined for all n > 0. 2 The Pigeonhole Principle and Ramsey Theory In an ancient. 22 Named after Lothar Collatz …
2013/03/22 — A Collatz sequence is a sequence formed by iteratively applying the function defined for the Collatz problem to a … (the Collatz[n] command needs to be defined by the user; the program will complain about division by zero but …
2019/12/09 — Herein we check the Collatz conjecture using only Typescript’s type system. … Anything divided by zero is undefined; Zero divided by a positive number is zero; Each time we can subtract B from A, we add one to the result; that …
Title page of Leonhard Euler, Vollständige Anleitung zur Algebra, Vol. 1 (edition of 1771, first published in 1770), and p. 34 from Article 83, where Euler explains why a number divided by zero gives infinity.
何とゼロ除算は、可能になるだろうと April 12, 2011 に 公に 予想されていたことを 発見した。
多くの数学で できないが、できるようになってきた経緯から述べられたものである。
Dividing by Nothing
by Alberto Martinez
It is well known that you cannot divide a number by zero. Math teachers write, for example, 24 ÷ 0 = undefined.
After all, other operations that seemed impossible for centuries, such as subtracting a greater number from a lesser, or taking roots of negative numbers, are now common. In mathematics, sometimes the impossible becomes possible, often with good reason.
George Gamow (1904-1968) Russian-born American nuclear physicist and cosmologist remarked that “it is well known to students of high school algebra” that division by zero is not valid; and Einstein admitted it as {\bf the biggest blunder of his life} [1]：
1. Gamow, G., My World Line (Viking, New York). p 44, 1970.
ICDDEA: International Conference on Differential & Difference Equations and Applications Differential and Difference Equations with Applications ICDDEA, Amadora, Portugal, June 2017 • Editors
• (view affiliations) • Sandra Pinelas • Tomás Caraballo • Peter Kloeden • John R. Graef Conference proceedingsICDDEA 2017
Impact of ‘Division by Zero’ in Einstein’s Static Universe and …
gsjournal.net/Science-Journals/…/Download/2084
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Impact of ‘Division by Zero’ in Einstein’s Static Universe and Newton’s Equations in Classical Mechanics. Ajay Sharma physicsajay@yahoo.com. Community Science Centre. Post Box 107 Directorate of Education Shimla 171001 India.
The division by zero is uniquely and reasonably determined as 1/0=0/0=z/0=0 in the natural extensions of fractions. We have to change our basic ideas for our space and world:
Division by Zero z/0 = 0 in Euclidean Spaces
Hiroshi Michiwaki, Hiroshi Okumura and Saburou Saitoh
International Journal of Mathematics and Computation Vol. 28(2017); Issue 1, 2017), 1-16.
List of division by zero: L. P. Castro and S. Saitoh, Fractional functions and their representations, Complex Anal. Oper. Theory {\bf7} (2013), no. 4, 1049-1063. M. Kuroda, H. Michiwaki, S. Saitoh, and M. Yamane, New meanings of the division by zero and interpretations on $100/0=0$ and on $0/0=0$, Int. J. Appl. Math. {\bf 27} (2014), no 2, pp. 191-198, DOI: 10.12732/ijam.v27i2.9. T. Matsuura and S. Saitoh, Matrices and division by zero z/0=0, Advances in Linear Algebra \& Matrix Theory, 2016, 6, 51-58 Published Online June 2016 in SciRes. http://www.scirp.org/journal/alamt \\ http://dx.doi.org/10.4236/alamt.201…. T. Matsuura and S. Saitoh, Division by zero calculus and singular integrals. (Differential and Difference Equations with Applications. Springer Proceedings in Mathematics \& Statistics.) T. Matsuura, H. Michiwaki and S. Saitoh, $\log 0= \log \infty =0$ and applications. (Submitted for publication). H. Michiwaki, S. Saitoh and M.Yamada, Reality of the division by zero $z/0=0$. IJAPM International J. of Applied Physics and Math. 6(2015), 1–8. http://www.ijapm.org/show-63-504-1…. H. Michiwaki, H. Okumura and S. Saitoh, Division by Zero $z/0 = 0$ in Euclidean Spaces, International Journal of Mathematics and Computation, 28(2017); Issue 1, 2017), 1-16. H. Okumura, S. Saitoh and T. Matsuura, Relations of $0$ and $\infty$, Journal of Technology and Social Science (JTSS), 1(2017), 70-77. S. Pinelas and S. Saitoh, Division by zero calculus and differential equations. (Differential and Difference Equations with Applications. Springer Proceedings in Mathematics \& Statistics). S. Saitoh, Generalized inversions of Hadamard and tensor products for matrices, Advances in Linear Algebra \& Matrix Theory. {\bf 4} (2014), no. 2, 87–95. http://www.scirp.org/journal/ALAMT/ S. Saitoh, A reproducing kernel theory with some general applications, Qian,T./Rodino,L.(eds.): Mathematical Analysis, Probability and Applications – Plenary Lectures: Isaac 2015, Macau, China, Springer Proceedings in Mathematics and Statistics, {\bf 177}(2016), 151-182. (Springer) .
Title page of Leonhard Euler, Vollständige Anleitung zur Algebra, Vol. 1 (edition of 1771, first published in 1770), and p. 34 from Article 83, where Euler explains why a number divided by zero gives infinity.
Algebraic division by zero implemented as quasigeometric multiplication by infinity in real and complex multispatial hyperspaces Author: Jakub Czajko, 92(2) (2018) 171-197 WSN 92(2) (2018) 171-197
L. P. Castro and S. Saitoh, Fractional functions and their representations, Complex Anal. Oper. Theory {\bf7} (2013), no. 4, 1049-1063.
M. Kuroda, H. Michiwaki, S. Saitoh, and M. Yamane,
New meanings of the division by zero and interpretations on $100/0=0$ and on $0/0=0$, Int. J. Appl. Math. {\bf 27} (2014), no 2, pp. 191-198, DOI: 10.12732/ijam.v27i2.9.
T. Matsuura and S. Saitoh,
Matrices and division by zero z/0=0,
Advances in Linear Algebra \& Matrix Theory, 2016, 6, 51-58
Division by zero calculus and singular integrals. (Submitted for publication).
T. Matsuura, H. Michiwaki and S. Saitoh,
$\log 0= \log \infty =0$ and applications. (Differential and Difference Equations with Applications. Springer Proceedings in Mathematics \& Statistics.)
International Journal of Mathematics and Computation, 28(2017); Issue 1, 2017), 1-16.
H. Okumura, S. Saitoh and T. Matsuura, Relations of $0$ and $\infty$,
Journal of Technology and Social Science (JTSS), 1(2017), 70-77.
S. Pinelas and S. Saitoh,
Division by zero calculus and differential equations. (Differential and Difference Equations with Applications. Springer Proceedings in Mathematics \& Statistics).
S. Saitoh, Generalized inversions of Hadamard and tensor products for matrices, Advances in Linear Algebra \& Matrix Theory. {\bf 4} (2014), no. 2, 87–95. http://www.scirp.org/journal/ALAMT/
S. Saitoh, A reproducing kernel theory with some general applications,
Qian,T./Rodino,L.(eds.): Mathematical Analysis, Probability and Applications – Plenary Lectures: Isaac 2015, Macau, China, Springer Proceedings in Mathematics and Statistics, {\bf 177}(2016), 151-182. (Springer) .
For Fundamental of Mathematics, I think the division by zero was known as the generalized Moore-Penrose solution of the fundamental equation: ax=b. Please look the simple evidence of its importance: viXra:2010.0228 submitted on 2020-10-28 21:39:06,
I think our mathematics is not complete still in a serious sense.May I hear your kind comments and suggestions on my idea? Saburou Saitoh2021.1.10.07:55
I am surprised to have your mail again. I am happy and fully convinced with the great work of scholars Brahmagupta, Bhaskara II, Mahavira, Aristotle, Cauchy, Weierstrass, Euler, Newton, Bernoulli, and their numerous followers. They laid the correct foundation of Mathematics by showing that 0/0 is indeterminant, i.e., it is defined only in the limiting sense.
The Isabelle[a]automated theorem prover is a higher-order logic (HOL) theorem prover, written in Standard ML and Scala. As an LCF-style theorem prover, it is based on a small logical core (kernel) to increase the trustworthiness of proofs without requiring — yet supporting — explicit proof objects.Isabelle is available inside a flexible system framework allowing for logically safe extensions, which comprise both theories as well as implementations for code-generation, documentation, and specific support for a variety of formal methods. It can be seen as an IDE for formal methods. In recent years, a substantial number of theories and system extensions have been collected in the Isabelle Archive of Formal Proofs (Isabelle AFP)[2]
For Fundamental of Mathematics, I think the division by zero was known as the generalized Moore-Penrose solution of the fundamental equation: ax=b. Please look the simple evidence of its importance: viXra:2010.0228 submitted on 2020-10-28 21:39:06,
I think our mathematics is not complete still in a serious sense.May I hear your kind comments and suggestions on my idea? Saburou Saitoh2021.1.10.07:55
I am surprised to have your mail again. I am happy and fully convinced with the great work of scholars Brahmagupta, Bhaskara II, Mahavira, Aristotle, Cauchy, Weierstrass, Euler, Newton, Bernoulli, and their numerous followers. They laid the correct foundation of Mathematics by showing that 0/0 is indeterminant, i.e., it is defined only in the limiting sense.
At 2024.2.4.7:22 We heard and obtained the response: What are the applications of real.div in Lean?
London Clark
Knowledge Empress
1. Mathematical Calculations: The real.div function in Lean is used for performing division operations on real numbers. It can be used for various mathematical calculations such as finding the quotient of two real numbers, calculating the reciprocal of a real number, and solving equations involving division.
2. Geometry: The real.div function can be used in geometry to find the ratio of two quantities, such as the ratio of the circumference to the diameter of a circle (π).
3. Physics: In physics, the real.div function can be used to calculate physical quantities such as velocity, acceleration, and force, which involve division operations.
4. Financial Calculations: The real.div function can be used in financial calculations, such as calculating interest rates, compound interest, and mortgage payments.
5. Statistical Analysis: In statistics, the real.div function can be used to calculate various measures, such as the mean, median, and standard deviation, which involve division operations.
6. Machine Learning: In machine learning, the real.div function can be used to normalize data, which involves dividing the data by its mean or standard deviation.
7. Game Development: The real.div function can be used in game development to calculate the movement of objects, such as projectiles, based on their velocity and acceleration.
8. Cryptography: In cryptography, the real.div function can be used to perform operations on large prime numbers, which are often used in encryption algorithms.
9. Control Systems: The real.div function can be used in control systems to calculate transfer functions, which are used to model the behavior of physical systems.
10. Signal Processing: In signal processing, the real.div function can be used to calculate the frequency response of a system, which is used to analyze and manipulate signals. Have you ever wondered about the various applications of real.div in Lean? Explore the possibilities and dive deeper into this topic by clicking on the link in our bio.
Many proof assistants, such as Coq and Lean, define 1/0 = 0. This is due to the requirement that all functions are total. Such a definition does not create contradictions, as further manipulations (such as cancelling out) still require that the divisor is non-zero.[33][34]
Tanter, Éric; Tabareau, Nicolas (2015), “Gradual certified programming in coq”, DLS 2015: Proceedings of the 11th Symposium on Dynamic Languages, Association for Computing Machinery, arXiv:1506.04205, doi:10.1145/2816707.2816710, The standard division function on natural numbers in Coq, div, is total and pure, but incorrect: when the divisor is 0, the result is 0.
The Isabelle[a]automated theorem prover is a higher-order logic (HOL) theorem prover, written in Standard ML and Scala. As an LCF-style theorem prover, it is based on a small logical core (kernel) to increase the trustworthiness of proofs without requiring — yet supporting — explicit proof objects.Isabelle is available inside a flexible system framework allowing for logically safe extensions, which comprise both theories as well as implementations for code-generation, documentation, and specific support for a variety of formal methods. It can be seen as an IDE for formal methods. In recent years, a substantial number of theories and system extensions have been collected in the Isabelle Archive of Formal Proofs (Isabelle AFP)[2]
However, it has been denied since Aristotle (384 BC-322 BC), including the mistake of genius Euler, and does not include division by zero, which is said to have been a concern for Einstein’s life. A regrettable math. The four arithmetic operations were incomplete. Therefore, the following formula should be the equation following 17.
Dividing by Zero in Five Levels — Elementary to Math Major
The Institute of Reproducing Kernels is dealing with the theory of division by zero calculus and declares that the division by zero was discovered as $0/0=1/0=z/0=0$ in a natural sense on 2014.2.2. The result shows a new basic idea on the universe and space since Aristotele (BC384 – BC322) and Euclid (BC 3 Century – ), and the division by zero is since Brahmagupta (598 – 668 ?).
Announcement 478: Who did derive first the division by zero 1/0 and the division by zero calculus $\tan(\pi/2)=0, \log 0=0$ as the outputs of a computer?
For Fundamental of Mathematics, I think the division by zero was known as the generalized Moore-Penrose solution of the fundamental equation: ax=b. Please look the simple evidence of its importance: viXra:2010.0228 submitted on 2020-10-28 21:39:06,
I think our mathematics is not complete still in a serious sense.May I hear your kind comments and suggestions on my idea? Saburou Saitoh2021.1.10.07:55
rkernel 