Description: Atom exchange combined with contraposition. (Contributed by NM, 13-Jun-2012)
Ref | Expression | ||
---|---|---|---|
Hypotheses | 3noncol.l | ||
3noncol.j | |||
3noncol.a | |||
Assertion | hlatcon3 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 3noncol.l | ||
2 | 3noncol.j | ||
3 | 3noncol.a | ||
4 | 1 2 3 | 3noncolr2 | |
5 | 4 | simprd |