proposition: Lemma totakeK (T : eqType) (m : nat) (t1 t2 : m.-tuple T) : totake (teocat t1 t2) = t2.
proof: Proof. by apply/val_eqP; rewrite /= totakeE /= otake_eocat // !size_tuple. Qed.
imports: mathcomp(all_ssreflect perm algebra.zmodp) mathcomp(zify)