(256^n)-1 is always divisible by 17?
yes you can use recursivity to demonstrate it 256^(n+1) -1
Proof by induction:
n = 1: 256^1 - 1 → 255 → 15*17 hence divisible by 17
n → n+1: 256^(n+1) - 1 - (256^n - 1) → 256^n*(256 - 1) → 256^n*15*17 hence divisible by 17
