Theorem wl-impchain-a1-3

Description: Inference rule, a copy of a1dd . A recursive proof depending on previous instances, and demonstrating the proof pattern. (Contributed by Wolf Lammen, 20-Jun-2020) (New usage is discouraged.) (Proof modification is discouraged.)

	Ref	Expression
Hypothesis	wl-impchain-a1-3.a	⊢ ( 𝜑 → ( 𝜓 → 𝜒 ) )
Assertion	wl-impchain-a1-3	⊢ ( 𝜑 → ( 𝜓 → ( 𝜃 → 𝜒 ) ) )

Proof

Step	Hyp	Ref	Expression
1		wl-impchain-a1-3.a	⊢ ( 𝜑 → ( 𝜓 → 𝜒 ) )
2	1	wl-impchain-a1-2	⊢ ( 𝜑 → ( 𝜃 → ( 𝜓 → 𝜒 ) ) )
3	2	wl-impchain-com-2.3	⊢ ( 𝜑 → ( 𝜓 → ( 𝜃 → 𝜒 ) ) )