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I have no idea where the name "prime" came from, but.... there are certain numbers that are "odd".

These numbers are whole numbers that cannot be devised.

For instance, 5. The only way you can successfully divide 5 by anything is by 1 and 5.

Same with 7. Same with 31.

These are called "Prime Numbers" and no-one knows where they came from.

We do know that there are infinitely many of them. It is easy to prove. Take any number, multiply it by all the numbers below it and then add 1. Instant prime number.

The problem was, is, always has been, and wioll haven be, however high the prime number, which one is next?

There have been many theorems to calculate the "distribution" of the primes. One of the greatest books ever to confront this problem was "The Lore of the Primes", a book long since out of print.

There are several formulae to predict the "average" distribution, but NO-ONE has ever been able to predict "the next one".

A subject of long fascination for mathematicians and non-mathematicians alike.

Interestingly, the subject has become under increasing scrutiny from the US government, as a means to ensure security. It's name has become "Public Key Cryptography" - a name which basically means "you can't decode this".

It's basis is simple: Take two really large prime numbers (at least 99 digits each)and multiply them.

The result is a number at least 200 digits long, but is only divisible by the two numbers you first thought of.

To find out those first two numbers, it would require 15 billion Cray XM-P computers working at twice the age of the Universe at triple speed with double entendres.

To say the least, if not less.