Description: The set of homeomorphisms is a function on topologies. (Contributed by Mario Carneiro, 23-Aug-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | hmeofn | ⊢ Homeo Fn ( Top × Top ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-hmeo | ⊢ Homeo = ( 𝑗 ∈ Top , 𝑘 ∈ Top ↦ { 𝑓 ∈ ( 𝑗 Cn 𝑘 ) ∣ ◡ 𝑓 ∈ ( 𝑘 Cn 𝑗 ) } ) | |
| 2 | ovex | ⊢ ( 𝑗 Cn 𝑘 ) ∈ V | |
| 3 | 2 | rabex | ⊢ { 𝑓 ∈ ( 𝑗 Cn 𝑘 ) ∣ ◡ 𝑓 ∈ ( 𝑘 Cn 𝑗 ) } ∈ V | 
| 4 | 1 3 | fnmpoi | ⊢ Homeo Fn ( Top × Top ) |