gcd                     Find the Greatest Common Divisor, Smallest
                        Common Multiple, or Coprimality
generate_n_primes       Generate a Sequence of Prime Numbers
is_prime                Test for Prime Numbers
k_tuple                 Prime _k_-tuples
next_prime              Find the Next and Previous Prime Numbers
nth_prime               Get the n-th Prime from the Sequence of Primes.
prime_count             Prime-counting Functions and Estimating the
                        Value of the n-th Prime
primes                  Pre-computed Prime Numbers
primorial               Compute the Primorial
