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Cryptokyo TMUA Problem Set · Q11

Logic & proofNumber & counting

Find a counter-example to the statement: if pp is prime then 2p−12^p-1 is prime.

Ap=2p=2
Bp=3p=3
Cp=7p=7
Dp=11p=11
Ep=13p=13
Fp=23p=23

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