proposition: Lemma inc_inj : {mono f : x y / x <= y} -> injective f.
proof: Proof. exact: mono_inj. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)