proposition: Lemma coprimep_pexpl k m n : 0 < k -> coprimep (m ^+ k) n = coprimep m n.
proof: Proof. case: k => // k _; elim: k => [|k IHk]; first by rewrite expr1. by rewrite exprS coprimepMl -IHk andbb. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop ssralg poly)