← All posts tagged math

Свежачок: "Yitang Zhang, a lecturer at the University of New Hampshire, showed that even though primes get increasingly rare as you go further out along the number line, you will never stop finding pairs of primes separated by at most 70 million. His finding was the first time anyone had managed to put a finite bound on the gaps between prime numbers, representing a major leap toward proving the centuries-old twin primes conjecture, which posits that there are infinitely many pairs of primes separated by only two (such as 11 and 13)." wired.com

«Random number spotters will enjoy ‘A Million Random Digits with 100,000 Normal Deviates’, published by RAND in 1955. The book contains 600 pages of random digits neatly aligned in tables. The tables were designed to be used in mathematical and scientific experiments particularly in the area of cryptography. The book was reissued in 2001 and is available at Amazon»
dataisnature.com

$81.01 :)

Великолепная цитата:
«The fake philosophical terminology of mathematical logic has misled philosophers into believing that mathematical logic deals with the truth in the philosophical sense. But this is a mistake. Mathematical logic deals not with the truth, but with the game of truth.»

(c) Rota «The Pernicious Influence of Mathematics upon Philosophy»

Забавно:
«Now, Nikolaos Bardis of the University of Military Education, in Vari, Greece and colleagues there and at the Polytechnic Institute of Kiev, in Ukraine, have developed an innovative approach to logins, which implements the advanced concept of zero knowledge identification. The system is based on a set of relatively simple mathematical functions, known as one-way Boolean operators, to verify a login rather than the standard encryption-decryption calculations used today. The team explains that preliminary testing shows that their approach to a login algorithm could be hundreds or thousands of times faster than conventional logins. Importantly, the system will reduce the overall computing requirements on the provider side of the system as well as making logins much more secure.»

Simple arithmetic for faster, more secure websites alphagalileo.org

Я вот люблю иногда для разминки ума порешать какие-нибудь программерские задачи вида «очередной сфероконь в вакууме», математическими тоже не брезгую(они обычно пересекаются с программерскими). Собственно, если есть ещё любители такого вида досуга, то посоветуйте сайты, откуда вы берёте задачи, буду крайне благодарен.
Мой список:
projecteuler.net
geeksforgeeks.org
cm.baylor.edu
code.google.com
programmingpraxis.com

Сегодня я понял, как зарождается математическое мышление. Ехал сегодня в маршрутке на работу и слушал прелестнейший разговор двух детей на вид лет 7ми-8ми:
1ый: Когда я стану большим, я буду выше дома.
2ой: А я вырасту до неба.
1ый: А я выше неба.
2ой: Что бы ты не говорил, я буду на голову выше тебя.

Молодец, 2ой, создал функцию f(x) -> x + C и уделал первого.
Вопрос: какое значение x нужно назвать первому, чтобы не проиграть второму? (:

"During World War II, Allied forces readily admitted German tanks were superior to their own. The big question for Allied forces, then, was how many tanks Germany was producing. Knowing that would help them counter the threat. Here’s how they reverse-engineered serial numbers to find out.
To solve the problem of determining production numbers, Allied forces initially tried conventional intelligence gathering: spying, intercepting and decoding transmissions and interrogating captured enemies.
Using these methods, the Allies deduced that the German military industrial complex churned out around 1,400 tanks each month from June 1940 through September 1942."

How Allies Used Math Against German Tanks wired.com

One of the most common -and unfounded- reasons as to why Nobel decided against a Nobel prize in math is that [a woman he proposed to/his wife/his mistress] [rejected him because of/cheated him with] a famous mathematician. Gosta Mittag-Leffler is often claimed to be the guilty party. nobelprizes.com

Имхо, это явное деление на 0.

"I just returned from Paris where I was visiting the INRIA πr² team. It was a great visit, everyone was very hospitable, the food was great, and the weather was nice. I spoke at their seminar where I presented a new programming language eff which is based on the idea that computational effects are algebras. The language has been designed and implemented jointly by Matija Pretnar and myself. Eff is far from being finished, but I think it is ready to be shown to the world. What follows is an extended transcript of the talk I gave in Paris. It is divided into two posts. The present one reviews the basic theory of algebras for a signature and how they are related to computational effects. The impatient readers can skip ahead to the second part, which is about the programming language." math.andrej.com

The P=NP Question and Gödel’s Lost Letter covers historical developments (including the Gödel’s Lost letter), the importance of P=NP and the future of P=NP. This guide is also based on a new blog by the author, located at rjlipton.wordpress.com. Jin-Yi Cai, a Professor in computer science at the University of Wisconsin remarks 'I think it is the single most interesting web blog I have seen on related topics. He has a great insight and wit and beautiful way to see things and explain them.' Richard DeMillo, a professor in computer science at Georgia Tech remarks, 'This is a much needed treatment of great open problem computing.' amazon.com
...
My Book On P=NP Is Now Available rjlipton.wordpress.com

"It's incredible. I'm a Liberal Arts guy — undergrad in English, studying for an MLIS degree — and this experiment in broadening my horizons has really caught me off guard."
...
"Why, for fuck's sake, isn't geometry presented to children in these terms? Maybe I just had the worst math education of all time, but the only thing I remember from gradeschool geometry was page after page of meaningless problems presented with instructions, but without context. There was no effort made to present the logical reasoning behind the various concepts, it was just "Okay, memorize these formulas, do the even numbered problems from page 125, and leave me the hell alone.""
reddit.com

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