fact: Fixpoint bt_insert s t : bt := match t with | ∅ => s⪧∅ | t⪧u => match bt_lt_eq_lt_dec s t with | inleft (left _) => s⪧t⪧u | inleft (right _) => t⪧u | inright _ => t⪧(s→u) end end where "s → t" := (bt_insert s t).
imports: List Arith Lia Max Wellfounded Setoid Eqdep_dec Undecidability.Shared.Libs.DLW.Utils(utils_tac utils_list utils_decidable finite seteq) Undecidability.Shared.Libs.DLW.Vec(pos) Undecidability.Shared.Libs.DLW.Wf(wf_finite wf_chains) Undecidability.FOL.TRAKHTENBROT(notations fol_ops)