proposition: Lemma pnatE pi p : prime p -> pi.-nat p = (p \in pi).
proof: Proof. by move=> pr_p; rewrite /pnat prime_gt0 ?primes_prime //= andbT. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(fintype div bigop)