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Description: Reverse closure for the limit point predicate. (Contributed by Mario Carneiro, 9-Apr-2015) (Revised by Stefan O'Rear, 9-Aug-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | flimtop | ⊢ ( 𝐴 ∈ ( 𝐽 fLim 𝐹 ) → 𝐽 ∈ Top ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eqid | ⊢ ∪ 𝐽 = ∪ 𝐽 | |
| 2 | 1 | elflim2 | ⊢ ( 𝐴 ∈ ( 𝐽 fLim 𝐹 ) ↔ ( ( 𝐽 ∈ Top ∧ 𝐹 ∈ ∪ ran Fil ∧ 𝐹 ⊆ 𝒫 ∪ 𝐽 ) ∧ ( 𝐴 ∈ ∪ 𝐽 ∧ ( ( nei ‘ 𝐽 ) ‘ { 𝐴 } ) ⊆ 𝐹 ) ) ) |
| 3 | 2 | simplbi | ⊢ ( 𝐴 ∈ ( 𝐽 fLim 𝐹 ) → ( 𝐽 ∈ Top ∧ 𝐹 ∈ ∪ ran Fil ∧ 𝐹 ⊆ 𝒫 ∪ 𝐽 ) ) |
| 4 | 3 | simp1d | ⊢ ( 𝐴 ∈ ( 𝐽 fLim 𝐹 ) → 𝐽 ∈ Top ) |