proposition: Theorem Catalan_binE n : Catalan_bin n = Catalan n.
proof: Proof. by rewrite -card_bintreesz card_bintreesz_dyck card_Dyck_hsz. Qed.
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(div ssralg ssrint ssrnum binomial) tools combclass bintree