Perfect Power
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Detecting perfect powers is required by some factorization
algorithms. Currently `mpz_perfect_power_p' is implemented using
repeated Nth root extractions, though naturally only prime roots need
to be considered. (Note:Nth Root Algorithm.)
If a prime divisor p with multiplicity e can be found, then only
roots which are divisors of e need to be considered, much reducing the
work necessary. To this end divisibility by a set of small primes is
checked.