Description: The null set is a strictly monotone ordinal function. (Contributed by Andrew Salmon, 20-Nov-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | smo0 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ord0 | |
|
2 | 1 | iordsmo | |
3 | res0 | |
|
4 | smoeq | |
|
5 | 3 4 | ax-mp | |
6 | 2 5 | mpbi | |