Thread: Prove that it is composite number

I'm trying to solve some problem, but I don't have any good idea to do it
Prove that a²+b³+c⁶, where a,b,c are positive integers, is always composite number. Thanks for all help

Originally Posted by aleschio

Prove that a²+b³+c⁶, where a,b,c are positive integers, is always composite number. Thanks for all help

But it is not true: let .

And what if a,b and c is different from 1?