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Description: The domain of a strictly monotone ordinal function is an ordinal. (Contributed by Mario Carneiro, 12-Mar-2013)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | smodm2 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | smodm | ||
| 2 | fndm | ||
| 3 | ordeq | ||
| 4 | 2 3 | syl | |
| 5 | 4 | biimpa | |
| 6 | 1 5 | sylan2 |