Theorem nfae

Description: All variables are effectively bound in an identical variable specifier. Usage of this theorem is discouraged because it depends on ax-13 . (Contributed by Mario Carneiro, 11-Aug-2016) (New usage is discouraged.)

	Ref	Expression
Assertion	nfae	$$⊢Ⅎz\forall xx=y$$

Proof

Step	Hyp	Ref	Expression
1		hbae	$$⊢\forall xx=y\to \forall z\forall xx=y$$
2	1	nf5i	$$⊢Ⅎz\forall xx=y$$