proposition: Lemma monic_map p : p \is monic -> p^f \is monic.
proof: Proof. move/monicP=> mon_p; rewrite monicE. by rewrite lead_coef_map_eq mon_p /= rmorph1 ?oner_neq0. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype bigop finset tuple) mathcomp(div ssralg countalg binomial)