proposition: Lemma const_vec_eq {X : UU} {n : nat} (v : Vector X n) (e : X) (i : ⟦ n ⟧%stn) : v = const_vec e -> v i = e.
proof: Proof. intros eq. rewrite eq. reflexivity. Defined.
imports: UniMath.Foundations.PartA UniMath.Foundations.NaturalNumbers UniMath.MoreFoundations.PartA UniMath.MoreFoundations.Nat UniMath.MoreFoundations.Tactics UniMath.Combinatorics.StandardFiniteSets UniMath.Combinatorics.Vectors UniMath.Algebra.RigsAndRings UniMath.Algebra.IteratedBinaryOperations UniMath.Algebra.Matrix UniMath.Algebra.GaussianElimination.Auxiliary