proposition: Lemma mleadD_le p q : (mlead (p + q) <= mlead p `|` mlead q)%O.
proof: Proof. have [->|] := eqVneq (p+q) 0; first by rewrite mlead0 le0x. move/mlead_supp/msuppD_le; rewrite mem_cat => /orP[]. + by move/msupp_le_mlead=> h; apply/(le_trans h)/leUl. + by move/msupp_le_mlead=> h; apply/(le_trans h)/leUr. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(choice fintype tuple finfun bigop finset binomial) mathcomp(order fingroup perm ssralg zmodp poly ssrint) mathcomp(matrix vector) mathcomp(bigenough) ssrcomplements freeg