Description: The birthday function is a function. (Contributed by Scott Fenton, 14-Jun-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | bdayfun | |- Fun bday |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | bdayfo | |- bday : No -onto-> On |
|
2 | fofun | |- ( bday : No -onto-> On -> Fun bday ) |
|
3 | 1 2 | ax-mp | |- Fun bday |