Description: Define the filter generating function. (Contributed by Jeff Hankins, 3-Sep-2009) (Revised by Stefan O'Rear, 11-Jul-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-fg | ⊢ filGen = ( 𝑤 ∈ V , 𝑥 ∈ ( fBas ‘ 𝑤 ) ↦ { 𝑦 ∈ 𝒫 𝑤 ∣ ( 𝑥 ∩ 𝒫 𝑦 ) ≠ ∅ } ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 0 | cfg | ⊢ filGen | |
| 1 | vw | ⊢ 𝑤 | |
| 2 | cvv | ⊢ V | |
| 3 | vx | ⊢ 𝑥 | |
| 4 | cfbas | ⊢ fBas | |
| 5 | 1 | cv | ⊢ 𝑤 | 
| 6 | 5 4 | cfv | ⊢ ( fBas ‘ 𝑤 ) | 
| 7 | vy | ⊢ 𝑦 | |
| 8 | 5 | cpw | ⊢ 𝒫 𝑤 | 
| 9 | 3 | cv | ⊢ 𝑥 | 
| 10 | 7 | cv | ⊢ 𝑦 | 
| 11 | 10 | cpw | ⊢ 𝒫 𝑦 | 
| 12 | 9 11 | cin | ⊢ ( 𝑥 ∩ 𝒫 𝑦 ) | 
| 13 | c0 | ⊢ ∅ | |
| 14 | 12 13 | wne | ⊢ ( 𝑥 ∩ 𝒫 𝑦 ) ≠ ∅ | 
| 15 | 14 7 8 | crab | ⊢ { 𝑦 ∈ 𝒫 𝑤 ∣ ( 𝑥 ∩ 𝒫 𝑦 ) ≠ ∅ } | 
| 16 | 1 3 2 6 15 | cmpo | ⊢ ( 𝑤 ∈ V , 𝑥 ∈ ( fBas ‘ 𝑤 ) ↦ { 𝑦 ∈ 𝒫 𝑤 ∣ ( 𝑥 ∩ 𝒫 𝑦 ) ≠ ∅ } ) | 
| 17 | 0 16 | wceq | ⊢ filGen = ( 𝑤 ∈ V , 𝑥 ∈ ( fBas ‘ 𝑤 ) ↦ { 𝑦 ∈ 𝒫 𝑤 ∣ ( 𝑥 ∩ 𝒫 𝑦 ) ≠ ∅ } ) |