proposition: Lemma Mij_n0 n: Mi n 0 = catalan n.
proof: Proof. by rewrite TMi_eq_Tnk2 // Tnk2_n0. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype) mathcomp(ssrnat seq path div) mathcomp(fintype tuple finfun bigop finset binomial)