proposition: Fact bt_cls_hfs_repr s : bt_cls (hfs_repr s) = s.
proof: Proof. destruct s as (t & Ht); simpl. apply bt_norm_exist, Ht. Qed.
imports: List Arith Lia Max Wellfounded Setoid Eqdep_dec Bool Undecidability.Shared.Libs.DLW.Utils(utils_tac utils_list finite) Undecidability.Shared.Libs.DLW.Vec(pos vec) Undecidability.Shared.Libs.DLW.Wf(wf_finite wf_chains) Undecidability.FOL.TRAKHTENBROT(notations fol_ops membership btree)