Description: Set exponentiation has a universal domain. (Contributed by NM, 8-Dec-2003) (Revised by Mario Carneiro, 8-Sep-2013)
Ref | Expression | ||
---|---|---|---|
Assertion | fnmap | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-map | |
|
2 | mapex | |
|
3 | 2 | el2v | |
4 | 1 3 | fnmpoi | |