Description: The birthday function is a function over No . (Contributed by Scott Fenton, 30-Jun-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | bdayfn | |- bday Fn No |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | bdayfo | |- bday : No -onto-> On |
|
2 | fofn | |- ( bday : No -onto-> On -> bday Fn No ) |
|
3 | 1 2 | ax-mp | |- bday Fn No |