Exercise

If g is primitive modulo p and a is an integer then g^a is also primitive if and only if gcd(a,p-1) = 1. This follows from

the theorem on page 3 of Section 2.1 and the theorem on page 1 of Section 2.2.

the Chinese remainder theorem on page 3 of Section 2.2.

Fermat's little theorem on page 1 of Section 2.4.

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