{A : Sequence} (x : sig A) : sig A. Proof. destruct x as [n a]; exact (n.+1; a^+). Defined.
Require Import Basics. Require Import Types. Require Import Diagrams.Diagram. Require Import Diagrams.Sequence. Require Import Diagrams.Cocone. Require Import Colimits.Colimit. Require Import Spaces.Nat.Core. Require Import Homotopy.IdentitySystems.