forall x, E x. Proof. intros [x y]; apply seq_colim_sum_ind_cur. 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.