(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Let n and k be integers with n>=2 and k>=2. Prove that (n-1)|(n^k - 1).

Hence prove that if n^k - 1 is prime then n=2 and k is prime.

2. Relevant equations

3. The attempt at a solution

I think you go about this question by using proof by induction. However im really not sure how to do this. Any help would be great! Thanks

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# Number theory - primes

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