proposition: Lemma map_polyC a : (a%:P)^f = (f a)%:P.
proof: Proof. by apply/polyP=> i; rewrite !(coef_map, coefC) -!mulrb raddfMn. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype bigop finset tuple) mathcomp(div ssralg countalg binomial)