Description: The topological indistinguishability map is a function on the base. (Contributed by Mario Carneiro, 25-Aug-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | kqval.2 | |- F = ( x e. X |-> { y e. J | x e. y } ) | |
| Assertion | kqffn | |- ( J e. V -> F Fn X ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | kqval.2 |  |-  F = ( x e. X |-> { y e. J | x e. y } ) | |
| 2 | ssrab2 |  |-  { y e. J | x e. y } C_ J | |
| 3 | elpw2g |  |-  ( J e. V -> ( { y e. J | x e. y } e. ~P J <-> { y e. J | x e. y } C_ J ) ) | |
| 4 | 2 3 | mpbiri |  |-  ( J e. V -> { y e. J | x e. y } e. ~P J ) | 
| 5 | 4 | adantr |  |-  ( ( J e. V /\ x e. X ) -> { y e. J | x e. y } e. ~P J ) | 
| 6 | 5 1 | fmptd | |- ( J e. V -> F : X --> ~P J ) | 
| 7 | 6 | ffnd | |- ( J e. V -> F Fn X ) |