proposition: Lemma lt_sorted_eq s1 s2 : sorted <%O s1 -> sorted <%O s2 -> s1 =i s2 -> s1 = s2.
proof: Proof. exact/irr_sorted_eq/ltxx/lt_trans. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)