proposition: Fact ra_rel_fix_comp k i f gj : [| @ra_comp k i f gj |] = s_comp [|f|] (vec_map (fun x => [|x|]) gj).
proof: Proof. simpl ra_rel; f_equal. apply vec_pos_ext; intros p. rewrite vec_pos_set, vec_pos_map; trivial. Qed.
imports: Arith Lia List Bool Eqdep_dec Undecidability.Shared.Libs.DLW(utils_tac utils_nat utils_list finite pos vec) Undecidability.MuRec.MuRec