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Description: Define the function that associates with a set the set of topologies on it. (Contributed by Stefan O'Rear, 31-Jan-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-topon | ⊢ TopOn = ( 𝑏 ∈ V ↦ { 𝑗 ∈ Top ∣ 𝑏 = ∪ 𝑗 } ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | ctopon | ⊢ TopOn | |
| 1 | vb | ⊢ 𝑏 | |
| 2 | cvv | ⊢ V | |
| 3 | vj | ⊢ 𝑗 | |
| 4 | ctop | ⊢ Top | |
| 5 | 1 | cv | ⊢ 𝑏 |
| 6 | 3 | cv | ⊢ 𝑗 |
| 7 | 6 | cuni | ⊢ ∪ 𝑗 |
| 8 | 5 7 | wceq | ⊢ 𝑏 = ∪ 𝑗 |
| 9 | 8 3 4 | crab | ⊢ { 𝑗 ∈ Top ∣ 𝑏 = ∪ 𝑗 } |
| 10 | 1 2 9 | cmpt | ⊢ ( 𝑏 ∈ V ↦ { 𝑗 ∈ Top ∣ 𝑏 = ∪ 𝑗 } ) |
| 11 | 0 10 | wceq | ⊢ TopOn = ( 𝑏 ∈ V ↦ { 𝑗 ∈ Top ∣ 𝑏 = ∪ 𝑗 } ) |