proposition: Lemma maxset_eq P1 P2 A : P1 =1 P2 -> maxset P1 A = maxset P2 A.
proof: Proof. by move=> eP12; apply: minset_eq => x /=; rewrite !unlock_with eP12. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop)