Description: The set of homeomorphisms is a function on topologies. (Contributed by Mario Carneiro, 23-Aug-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | hmeofn | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-hmeo | |
|
2 | ovex | |
|
3 | 2 | rabex | |
4 | 1 3 | fnmpoi | |