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by **james_bond** on Sun May 17, 2009 4:18 pm

For $a$ , $k$ , $n$ positive integers find $\gcd(a^n+1,a^k+1)$ .

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by **stapel_eliz** on Sun May 17, 2009 7:22 pm

I think the greatest common divisor will be 2 for odd values of "a", and 1 for even values of "a". But you probably need to prove this....

:popcorn:

by **Martingale** on Mon May 18, 2009 6:11 am

stapel_eliz wrote:I think the greatest common divisor will be 2 for odd values of "a", and 1 for even values of "a". But you probably need to prove this....

if a=5, n=7 and k=9..then the

gcd(5^7+1,5^9+1)=6

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Greatest common divisor of (a^n + 1, a^k + 1) for ints a,k,n

Greatest common divisor of (a^n + 1, a^k + 1) for ints a,k,n

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