fact: Definition M_M0 := pure_app (pure_var 0) (many_pure_term_abs (pure_var_bound M0) M0).
imports: List Lia Relation_Operators Undecidability.SystemF.SysF Undecidability.SystemF.Util(Facts poly_type_facts pure_term_facts term_facts typing_facts pure_typing_facts) ssreflect ssrbool ssrfun