Quote Originally Posted by Fynlar View Post
I still think it's crap that it isn't, to be honest. It's pretty similar to my feelings about how Pluto should still be a planet.
If you make 1 a prime it breaks a lot of theorems, but most importantly the fundamental theorem of arithmetic which states that every positive integer greater than one can be written uniquely as a product of primes. E.g. 2 x 3 = 6. Include 1 as a prime, and you end up with infinitely many products of primes for any positive integer. E.g. 1 x 2 x 3, 1 x 1 x 2 x 3, and so on.