Description: Alternate proof of r1om , shorter as a consequence of inar1 , but requiring AC. (Contributed by Mario Carneiro, 27-May-2013) (Proof modification is discouraged.) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | r1omALT | |- ( R1 ` _om ) ~~ _om |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | omina | |- _om e. Inacc |
|
2 | inar1 | |- ( _om e. Inacc -> ( R1 ` _om ) ~~ _om ) |
|
3 | 1 2 | ax-mp | |- ( R1 ` _om ) ~~ _om |