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Metamath Proof Explorer

Theorem nfaba1g

Description: Bound-variable hypothesis builder for a class abstraction. Usage of this theorem is discouraged because it depends on ax-13 . See nfaba1 for a version with a disjoint variable condition, but not requiring ax-13 . (Contributed by Mario Carneiro, 14-Oct-2016) (New usage is discouraged.)

		Ref	Expression
	Assertion	nfaba1g	⊢ Ⅎ 𝑥 { 𝑦 ∣ ∀ 𝑥 𝜑 }

Proof

Step	Hyp	Ref	Expression
1		nfa1	⊢ Ⅎ 𝑥 ∀ 𝑥 𝜑
2	1	nfabg	⊢ Ⅎ 𝑥 { 𝑦 ∣ ∀ 𝑥 𝜑 }