# Math Help - q?

1. ## q?

a) show that the converse of Fermat's Theorem is false.
b) n is an odd prime, then 2n l (2^(2n-1) - 2)

2. Originally Posted by Sally_Math
a) show that the converse of Fermat's Theorem is false.
Hint: $2^{341} \equiv 2(\bmod 341)$, now $341$ is not a prime.

b) n is an odd prime, then 2n l (2^(2n-1) - 2)
Hint: $2^{\phi(2n)} \equiv 1(\bmod 2n)$.