Specific Numbers
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Some say that numbers aren't as important as actual functions, but we say they are! :-) For anyone who has wondered why 13 is unlucky, why you can't eat pi, or why 1 is the multiplicative identity, this is the category you've been searching for since grade school. Whatever intellectual curiosity has been nagging at you since you first wrote the number 5, you will be likely to find an answer to your question here. And if not, submit your own! Also: Definitions of important constants, formulas to compute them and formulas that use them.

### Related categories3

37 Heaven
Collects information around the number thirty-seven.
Absolutely Abnormal Numbers
Published as math.NT/0006089, this note investigates numbers that are normal to no base whatsoever, and writes down explicitly such a number.
Arabic numerals
Describes the history of the Arabic numeral system that is in use nearly all over the world today.
Explains how these very large numbers (1 followed by a hundred zeroes, and 1 followed by a google of zeroes, respectively) were named. With links to references. From Swarthmore's Dr. Math.
Catalan Number -- MathWorld
Illustration of the Catalan numbers related to Euler's polygon division problem.
FAQ on Special Numbers
Fibonacci Numbers and the Golden section in Nature
Puzzles and things to do, for schools, teachers, colleges up to university level students, or just for recreation.
Indian numerals
Describes the history of the Indian numeral system.
Jewish Encyclopedia: Numbers and Numerals
Discusses the uses and symbolism of various numbers in Hebrew literature.
Mathematical Constants and Computation
RJN's More Digits of Irrational Numbers
Several million digits of e, and the square roots of 2, 3, 5, 6, 7, 8, and 10.
Stewy's Site
The infinitesimal is the opposite of infinity, and mathematicians still argue over its existence. This page probes into one of the weirdest numbers in mathematics.
Sum Beastliness
Some simple mathematics associated with 666, the Number of the Beast.
Timothy J. Warnock: Blog
Dedicated to the natural order of the universe and to the irrational and logical chaos it presents.
Triangular Numbers
Properties of triangular numbers including reversible, happy, harshad, highly composite, deficient, abundant ones.
Wikipedia - Mathematical constant
A list of constants with links to more detailed information.
World of Numbers
Includes a collection of randomly gathered numbers, curios, puzzles, palindromes and primes.

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Last update:
October 5, 2016 at 6:45:10 UTC
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