Hi,
On 12/09/10 04:33, ydegoyon@gmail.com wrote:
Mathieu Bouchard wrote:
On Sat, 11 Sep 2010, Kim Cascone wrote:
is there a Pd object for generating prime numbers? currently I'm: [1 2 3 5 7 9...97]
1 is not a prime number. (9 is not a prime number either)
i just read '1 is not a prime number' of course 9 is not, ut a prime number can only be divided by 1 and itself, so why 1 can't be?
1 is special and unique, it has only 1 factor (itself). I'd guess that 0 has an infinite number of factors, but I'm not sure on this. In any case it's probably special too.
Mathematicians almost all agree that 1 should not be classified as prime, because it does not have exactly 2 distinct factors. The main reason is that if you leave out the number 1 from the set of prime numbers, you can prove nice uniqueness theorems about prime factorization:
http://en.wikipedia.org/wiki/Fundamental_theorem_of_arithmetic
The name shows just how important that property is considered to be. The uniqueness of prime factorization can be used to show some quite impressive things, see for example:
http://en.wikipedia.org/wiki/Goedel_numbering
used to prove that "you can't prove everything" (or something along those lines, I've not studied this maths in enough depth).