Just a couple questions that I'd appreciate any help on.(adsbygoogle = window.adsbygoogle || []).push({});

1. if [(2^d) - 1] is prime, prove that d is prime as well.

2. Prove that (p-1)C(k) is congruent to (-1)^k mod p.

I've started them both but ended up getting stuck.

Any ideas?

Thanks

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# Prime proofs

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