Theorem wl-impchain-a1-2 33284

Description: Inference rule, a copy of a1d 25. First recursive proof based on the previous instance. (Contributed by Wolf Lammen, 20-Jun-2020.) (New usage is discouraged.) (Proof modification is discouraged.)

Hypothesis

Ref	Expression
wl-impchain-a1-2.a	|- ( ph -> ps )

Assertion

Ref	Expression
wl-impchain-a1-2	|- ( ph -> ( ch -> ps ) )

Proof of Theorem wl-impchain-a1-2

Step	Hyp	Ref	Expression
1		wl-impchain-a1-2.a	. . 3 |- ( ph -> ps )
2	1	wl-impchain-a1-1 33283	. 2 |- ( ch -> ( ph -> ps ) )
3	2	wl-impchain-com-1.2 33275	1 |- ( ph -> ( ch -> ps ) )

Syntax hints:   -> wi 4

This theorem was proved from axioms:  ax-mp 5  ax-luk1 33241  ax-luk2 33242  ax-luk3 33243

This theorem is referenced by:  wl-impchain-a1-3  33285