# Prove that it is composite number

• December 1st 2012, 08:08 AM
aleschio
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 :)
• December 1st 2012, 08:16 AM
Plato
Re: Prove that it is composite number
Quote:

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 $a=2,~b=2,~\&~c=1$.
• December 2nd 2012, 09:46 AM
aleschio
Re: Prove that it is composite number
And what if a,b and c is different from 1?