Theorem nfa1OLDOLD 2207

Description: Obsolete proof of nfa1 2028 as of 6-Oct-2021. (Contributed by Mario Carneiro, 11-Aug-2016.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
nfa1OLDOLD	|- F/ x A. x ph

Proof of Theorem nfa1OLDOLD

Step	Hyp	Ref	Expression
1		hba1 2151	. 2 |- ( A. x ph -> A. x A. x ph )
2	1	nfiOLD 1734	1 |- F/ x A. x ph

Syntax hints:   A.wal 1481   F/wnfOLD 1709

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-10 2019  ax-12 2047

This theorem depends on definitions:  df-bi 197  df-or 385  df-ex 1705  df-nf 1710  df-nfOLD 1721

This theorem is referenced by:  nfnf1OLDOLD  2208