Metamath Proof Explorer


Theorem sdomn2lp

Description: Strict dominance has no 2-cycle loops. (Contributed by NM, 6-May-2008)

Ref Expression
Assertion sdomn2lp ¬ A B B A

Proof

Step Hyp Ref Expression
1 sdomirr ¬ A A
2 sdomtr A B B A A A
3 1 2 mto ¬ A B B A