Theorem nfaba1OLD

Description: Obsolete version of nfaba1 as of 14-May-2025. (Contributed by Mario Carneiro, 14-Oct-2016) (Revised by Gino Giotto, 20-Jan-2024) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Assertion	nfaba1OLD	$$⊢\underset{\_}{Ⅎ}x\left\{y|\forall x\phi \right\}$$

Proof

Step	Hyp	Ref	Expression
1		nfa1	$$⊢Ⅎx\forall x\phi$$
2	1	nfab	$$⊢\underset{\_}{Ⅎ}x\left\{y|\forall x\phi \right\}$$