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#1 2019-01-13 03:29:21

Primenumbers
Member
Registered: 2013-01-22
Posts: 149

If 2p + 1 is a factor of 2^p - 1 then it is prime, proof.

If an integer, 2p + 1, where p is a prime number, is a divisor of the Mersenne number

, then 2p + 1 is a prime number.

My argument is that because divisors of the Mersenne number

can’t be < p if p is a prime number. Therefore if 2p +1 is a divisor of
it has no divisors as p is > the square root of 2p + 1. This will therefore make 2p + 1 a prime number.

Is this proof correct?

Last edited by Primenumbers (2019-01-13 03:42:20)


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