proposition: Lemma lt_Rank i : {mono @Rank i : j k / j < k}.
proof: Proof. by move=> j k; rewrite !ltNge le_Rank. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)