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

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

Postby james_bond on Sun May 17, 2009 4:18 pm

For , , positive integers find .
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Postby 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....

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Re:

Postby 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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