fact: Definition safe_poly_type (n: nat) (ts: list poly_type) (x: nat) := many_poly_abs n (many_poly_arr ts (poly_var (n + x))).
imports: PeanoNat List Lia Undecidability.SystemF.SysF Undecidability.SystemF.Autosubst.syntax Undecidability.SystemF.Util(Facts poly_type_facts term_facts typing_facts iipc2_facts sn_facts) Undecidability.DiophantineConstraints.H10C ssreflect ssrbool ssrfun