length_seq_rev'@{} (n : nat) : length (seq_rev' n) = n. Proof. induction n as [|n IHn]. 1: reflexivity. cbn; f_ap. lhs nrapply length_list_map. exact IHn. Defined.
Require Import Basics.Overture Basics.Tactics Basics.PathGroupoids Basics.Trunc Require Import Types.Paths Types.Unit Types.Prod Types.Sigma Types.Sum