proposition: Lemma sorted_subseq_sort_le s1 s2 : subseq s1 s2 -> sorted <=%O s1 -> subseq s1 (sort <=%O s2).
proof: Proof. exact/sorted_subseq_sort/le_trans/le_total. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)