fact: Definition ax_rep' phi := fun_rel' phi → ∀ ∃ ∀ $0 ∈' $1 ↔ ∃ $0 ∈' $3 ∧ phi[$0 .: $1 .: Nat.add 4 >> var].
imports: Undecidability.FOL.Utils.FullSyntax Undecidability.FOL.Sets.Signatures Undecidability.FOL.Sets.ZF List