Theorem wl-impchain-a1-1

Description: Inference rule, a copy of a1i . Head start of a recursive proof pattern. (Contributed by Wolf Lammen, 20-Jun-2020) (New usage is discouraged.) (Proof modification is discouraged.)

	Ref	Expression
Hypothesis	wl-impchain-a1-1.a	$$⊢\phi$$
Assertion	wl-impchain-a1-1	$$⊢\psi \to \phi$$

Proof

Step	Hyp	Ref	Expression
1		wl-impchain-a1-1.a	$$⊢\phi$$
2	1	wl-luk-a1i	$$⊢\psi \to \phi$$