(* QuickChick Prelude *)
Set Warnings "-extraction-opaque-accessed,-extraction".
Set Warnings "-notation-overridden,-parsing".
Set Bullet Behavior "Strict Subproofs".
(* End prelude *)
Require Export Poly.

Theorem silly1 : forall (n m o p : nat),
n = m  ->
[n;o] = [n;p] ->
[n;o] = [m;p].