# Mathematics

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Not to be confused with the " squeeze theorem " (sometimes called the "sandwich theorem"). In measure theory , a branch of mathematics , the ham sandwich theorem , also called the Stone–Tukey theorem after Arthur H.

The Wickr app.

## A new formula for avoiding supermarket queues

Supermarket queues are dreaded by many.

## - StumbleUpon

Perpetual Futility A short history of the search for perpetual motion. by Donald E. Simanek Popular histories too often present perpetual motion machines as "freaks and curiosities" of engineering without telling us just how they were understood at the time. They also fail to inform us that even in the earliest history of science and engineering, many persons were able to see the futility and folly of attempts to achieve perpetual motion. Sometimes a particular device comes to us with a label, such as "Bishop Wilkins' magnetic perpetual motion machine." Popular articles leave the impression that the inventor believed it was a perpetual motion machine.

## An Overview of Cryptography

What's Special About This Number? If you know a distinctive fact about a number not listed here, please e-mail me. primes graphs digits sums of powers bases combinatorics powers/polygonal Fibonacci
Lecture Slides Here are links to the PDF, PowerPoint and CSD ( Classroom Presenter ) files for the lecture slides. You may print a hardcopy of the slides to refer to during lecture. Audio and Video Archives On the day after the lecture, video archives will be posted here in a format suitable for both WebViewer , and Windows Media Player.

## Prime Time - Mathematicians have tried in vain to this day to discoversome oreder inthe sequence of prime numbers...

WHEN G. H. Hardy faced a stormy sea passage from Scandinavia to England, he took out an unusual insurance policy. Hardy scribbled a postcard to a friend with the words: "Have proved the Riemann hypothesis".

## Methods for Studying Coincidences | Wired Science | Wired.com

One of my favorite mathematics papers of all time is called “Methods for Studying Coincidences.” By Persi Diaconis and Frederick Mosteller, it aims to provide a rigorous mathematical framework for the study of coincidences.
Welcome! This is a collection of short articles designed to provide an introduction to the areas of modern mathematics and pointers to further information, as well as answers to some common (or not!) questions. The material is arranged in a hierarchy of disciplines, each with its own index page (" blue pages "). To reach the best page for your interests, use whichever of these navigation tools (" purple pages ") you prefer:

## Mathematical Atlas: A gateway to Mathematics

Poker is a card game played with a normal deck of 52 cards . Sometimes, additional cards called "jokers" are also used. In straight or draw poker, each player is normally dealt a hand of five cards. Depending on the variant, players then discard and redraw cards , trying to improve their hands. Bets are placed at each discard step.

## Poker -- from Wolfram MathWorld

Where I live in Saskatchewan, the weather changes every five minutes, so I have a habit of carrying a scarf with me, even in the warmer months. Despite spending nearly four decades in this blessed area of the world, though, I never learned how to tie a scarf properly until very recently. I am often fashion challenged in this way. I once wore a rope for a belt for several months. It’s true.

## Web Equation

Earth has a new reason to celebrate. It's looking like we will make it past Dec. 21, 2012. According to LiveScience , researchers have unearthed the oldest-known version of the ancient Maya calendar in the Guatemalan rainforest.

## Perfect numbers

Version for printing It is not known when perfect numbers were first studied and indeed the first studies may go back to the earliest times when numbers first aroused curiosity.

## Nerd Paradise : Calculating Base 10 Logarithms in Your Head

Calculating base 10 logarithms in your head on the fly is a lot easier than you may think. It is simply a matter of memorization and a little estimation... First memorize all the single digit base 10 logs.

## - StumbleUpon

The length of the polygonal spiral is found by noting that the ratio of inradius to circumradius of a regular polygon of sides is The total length of the spiral for an -gon with side length is therefore Consider the solid region obtained by filling in subsequent triangles which the spiral encloses.