so 1 is not a prime number mostly because it's very convenient

>>7971446
No

>>7971447
but why not? saying 1 is not a prime because primes are "a number greater than 1 that is only divisible by 1 and itself" is kinda like saying 9 is not divisible by 3 because numbers divisible by 3 are "a number greater than 9 that is divisible by 3".

>>7971446
>primes - four divisors
>1 - two divisors

>>7971450
Define prime numbers as the ones which have exactly 4 integer divisors.
There you are, no need to cry.

>>7971456
dude what i mean is that prime numbers are divisible by 1 and themselves. this includes 1 because it's divisible by 1 and itself, it's just that both those divisors happen to be the same number. the only thing that excludes 1 from being prime is that people say so

The only reason to say that 1 is not prime is so that then you can say "each prime as a unique prime factorisation"

Prove me wrong.
There is no genuine reason for it other than autism
> waaaahh 7 = 7*1 !! My autistic little weeny brain can't handle it waaahhhhhh

>>7971456
Integer divisors of 2:
1, 2
Therefore 2 is not a prime number.

Huuurrrr

>>7971446
It's in the definition of primes that they aren't units...

>>7971540
Go back to college

>>7971537
>prove me wrong
You're right, but I don't see why that is an issue. Why not make our definitions useful?

>>7971450
That's not the definition of prime (it's sort of the definition of irreducible, which is the same for integers, but you need to state it more precisely). A number [math] p \ne \pm 1 [/math] is prime if whenever [math]p \mid ab[/math,], either [math] p \mid a [/math] or [math] p \mid b [/math].

>>7971540
what about -1 and -2?

>>7971615
Only correct answer in this thread.