proposition: Fact erase_many_ty_abs {n P} : erase (many_ty_abs n P) = erase P.
proof: Proof. elim: n => /= *; by congruence. Qed.
imports: List Lia Undecidability.SystemF.SysF Undecidability.SystemF.Autosubst.syntax Undecidability.SystemF.Autosubst.unscoped Undecidability.SystemF.Util(Facts poly_type_facts pure_term_facts) ssreflect ssrbool ssrfun