Metamath Proof Explorer


Theorem an42s

Description: Inference rearranging 4 conjuncts in antecedent. (Contributed by NM, 10-Aug-1995)

Ref Expression
Hypothesis an41r3s.1 φψχθτ
Assertion an42s φχθψτ

Proof

Step Hyp Ref Expression
1 an41r3s.1 φψχθτ
2 1 an4s φχψθτ
3 2 ancom2s φχθψτ