| Step | Hyp | Ref | Expression | 
						
							| 1 |  | neibastop1.1 | ⊢ ( 𝜑  →  𝑋  ∈  𝑉 ) | 
						
							| 2 |  | neibastop1.2 | ⊢ ( 𝜑  →  𝐹 : 𝑋 ⟶ ( 𝒫  𝒫  𝑋  ∖  { ∅ } ) ) | 
						
							| 3 |  | neibastop1.3 | ⊢ ( ( 𝜑  ∧  ( 𝑥  ∈  𝑋  ∧  𝑣  ∈  ( 𝐹 ‘ 𝑥 )  ∧  𝑤  ∈  ( 𝐹 ‘ 𝑥 ) ) )  →  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  ( 𝑣  ∩  𝑤 ) )  ≠  ∅ ) | 
						
							| 4 |  | neibastop1.4 | ⊢ 𝐽  =  { 𝑜  ∈  𝒫  𝑋  ∣  ∀ 𝑥  ∈  𝑜 ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ } | 
						
							| 5 |  | neibastop1.5 | ⊢ ( ( 𝜑  ∧  ( 𝑥  ∈  𝑋  ∧  𝑣  ∈  ( 𝐹 ‘ 𝑥 ) ) )  →  𝑥  ∈  𝑣 ) | 
						
							| 6 |  | neibastop1.6 | ⊢ ( ( 𝜑  ∧  ( 𝑥  ∈  𝑋  ∧  𝑣  ∈  ( 𝐹 ‘ 𝑥 ) ) )  →  ∃ 𝑡  ∈  ( 𝐹 ‘ 𝑥 ) ∀ 𝑦  ∈  𝑡 ( ( 𝐹 ‘ 𝑦 )  ∩  𝒫  𝑣 )  ≠  ∅ ) | 
						
							| 7 | 1 2 3 4 | neibastop1 | ⊢ ( 𝜑  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 8 | 1 2 3 4 5 6 | neibastop2 | ⊢ ( ( 𝜑  ∧  𝑧  ∈  𝑋 )  →  ( 𝑛  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } )  ↔  ( 𝑛  ⊆  𝑋  ∧  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ ) ) ) | 
						
							| 9 |  | velpw | ⊢ ( 𝑛  ∈  𝒫  𝑋  ↔  𝑛  ⊆  𝑋 ) | 
						
							| 10 | 9 | anbi1i | ⊢ ( ( 𝑛  ∈  𝒫  𝑋  ∧  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ )  ↔  ( 𝑛  ⊆  𝑋  ∧  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ ) ) | 
						
							| 11 | 8 10 | bitr4di | ⊢ ( ( 𝜑  ∧  𝑧  ∈  𝑋 )  →  ( 𝑛  ∈  ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } )  ↔  ( 𝑛  ∈  𝒫  𝑋  ∧  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ ) ) ) | 
						
							| 12 | 11 | eqabdv | ⊢ ( ( 𝜑  ∧  𝑧  ∈  𝑋 )  →  ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } )  =  { 𝑛  ∣  ( 𝑛  ∈  𝒫  𝑋  ∧  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ ) } ) | 
						
							| 13 |  | df-rab | ⊢ { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ }  =  { 𝑛  ∣  ( 𝑛  ∈  𝒫  𝑋  ∧  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ ) } | 
						
							| 14 | 12 13 | eqtr4di | ⊢ ( ( 𝜑  ∧  𝑧  ∈  𝑋 )  →  ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) | 
						
							| 15 | 14 | ralrimiva | ⊢ ( 𝜑  →  ∀ 𝑧  ∈  𝑋 ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) | 
						
							| 16 |  | sneq | ⊢ ( 𝑥  =  𝑧  →  { 𝑥 }  =  { 𝑧 } ) | 
						
							| 17 | 16 | fveq2d | ⊢ ( 𝑥  =  𝑧  →  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } ) ) | 
						
							| 18 |  | fveq2 | ⊢ ( 𝑥  =  𝑧  →  ( 𝐹 ‘ 𝑥 )  =  ( 𝐹 ‘ 𝑧 ) ) | 
						
							| 19 | 18 | ineq1d | ⊢ ( 𝑥  =  𝑧  →  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  =  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 ) ) | 
						
							| 20 | 19 | neeq1d | ⊢ ( 𝑥  =  𝑧  →  ( ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅  ↔  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ ) ) | 
						
							| 21 | 20 | rabbidv | ⊢ ( 𝑥  =  𝑧  →  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) | 
						
							| 22 | 17 21 | eqeq12d | ⊢ ( 𝑥  =  𝑧  →  ( ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  ↔  ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 23 | 22 | cbvralvw | ⊢ ( ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  ↔  ∀ 𝑧  ∈  𝑋 ( ( nei ‘ 𝐽 ) ‘ { 𝑧 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑧 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) | 
						
							| 24 | 15 23 | sylibr | ⊢ ( 𝜑  →  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) | 
						
							| 25 |  | toponuni | ⊢ ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  →  𝑋  =  ∪  𝑗 ) | 
						
							| 26 |  | eqimss2 | ⊢ ( 𝑋  =  ∪  𝑗  →  ∪  𝑗  ⊆  𝑋 ) | 
						
							| 27 | 25 26 | syl | ⊢ ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  →  ∪  𝑗  ⊆  𝑋 ) | 
						
							| 28 |  | sspwuni | ⊢ ( 𝑗  ⊆  𝒫  𝑋  ↔  ∪  𝑗  ⊆  𝑋 ) | 
						
							| 29 | 27 28 | sylibr | ⊢ ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  →  𝑗  ⊆  𝒫  𝑋 ) | 
						
							| 30 | 29 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  𝑗  ⊆  𝒫  𝑋 ) | 
						
							| 31 |  | sseqin2 | ⊢ ( 𝑗  ⊆  𝒫  𝑋  ↔  ( 𝒫  𝑋  ∩  𝑗 )  =  𝑗 ) | 
						
							| 32 | 30 31 | sylib | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  ( 𝒫  𝑋  ∩  𝑗 )  =  𝑗 ) | 
						
							| 33 |  | topontop | ⊢ ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  →  𝑗  ∈  Top ) | 
						
							| 34 | 33 | ad3antlr | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  ∧  𝑜  ∈  𝒫  𝑋 )  →  𝑗  ∈  Top ) | 
						
							| 35 |  | eltop2 | ⊢ ( 𝑗  ∈  Top  →  ( 𝑜  ∈  𝑗  ↔  ∀ 𝑥  ∈  𝑜 ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 ) ) ) | 
						
							| 36 | 34 35 | syl | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  ∧  𝑜  ∈  𝒫  𝑋 )  →  ( 𝑜  ∈  𝑗  ↔  ∀ 𝑥  ∈  𝑜 ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 ) ) ) | 
						
							| 37 |  | elpwi | ⊢ ( 𝑜  ∈  𝒫  𝑋  →  𝑜  ⊆  𝑋 ) | 
						
							| 38 |  | ssralv | ⊢ ( 𝑜  ⊆  𝑋  →  ( ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  →  ∀ 𝑥  ∈  𝑜 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 39 | 37 38 | syl | ⊢ ( 𝑜  ∈  𝒫  𝑋  →  ( ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  →  ∀ 𝑥  ∈  𝑜 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 40 | 39 | adantl | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  →  ( ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  →  ∀ 𝑥  ∈  𝑜 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 41 |  | simprr | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) | 
						
							| 42 | 41 | eleq2d | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  ( 𝑜  ∈  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  ↔  𝑜  ∈  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 43 | 33 | ad3antlr | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  𝑗  ∈  Top ) | 
						
							| 44 | 25 | adantl | ⊢ ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  →  𝑋  =  ∪  𝑗 ) | 
						
							| 45 | 44 | sseq2d | ⊢ ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  →  ( 𝑜  ⊆  𝑋  ↔  𝑜  ⊆  ∪  𝑗 ) ) | 
						
							| 46 | 45 | biimpa | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ⊆  𝑋 )  →  𝑜  ⊆  ∪  𝑗 ) | 
						
							| 47 | 37 46 | sylan2 | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  →  𝑜  ⊆  ∪  𝑗 ) | 
						
							| 48 | 47 | sselda | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  𝑥  ∈  𝑜 )  →  𝑥  ∈  ∪  𝑗 ) | 
						
							| 49 | 48 | adantrr | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  𝑥  ∈  ∪  𝑗 ) | 
						
							| 50 | 47 | adantr | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  𝑜  ⊆  ∪  𝑗 ) | 
						
							| 51 |  | eqid | ⊢ ∪  𝑗  =  ∪  𝑗 | 
						
							| 52 | 51 | isneip | ⊢ ( ( 𝑗  ∈  Top  ∧  𝑥  ∈  ∪  𝑗 )  →  ( 𝑜  ∈  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  ↔  ( 𝑜  ⊆  ∪  𝑗  ∧  ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 ) ) ) ) | 
						
							| 53 | 52 | baibd | ⊢ ( ( ( 𝑗  ∈  Top  ∧  𝑥  ∈  ∪  𝑗 )  ∧  𝑜  ⊆  ∪  𝑗 )  →  ( 𝑜  ∈  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  ↔  ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 ) ) ) | 
						
							| 54 | 43 49 50 53 | syl21anc | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  ( 𝑜  ∈  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  ↔  ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 ) ) ) | 
						
							| 55 |  | pweq | ⊢ ( 𝑛  =  𝑜  →  𝒫  𝑛  =  𝒫  𝑜 ) | 
						
							| 56 | 55 | ineq2d | ⊢ ( 𝑛  =  𝑜  →  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  =  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 ) ) | 
						
							| 57 | 56 | neeq1d | ⊢ ( 𝑛  =  𝑜  →  ( ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 58 | 57 | elrab3 | ⊢ ( 𝑜  ∈  𝒫  𝑋  →  ( 𝑜  ∈  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 59 | 58 | ad2antlr | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  ( 𝑜  ∈  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 60 | 42 54 59 | 3bitr3d | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ( 𝑥  ∈  𝑜  ∧  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) )  →  ( ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 61 | 60 | expr | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  𝑥  ∈  𝑜 )  →  ( ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  →  ( ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) ) | 
						
							| 62 | 61 | ralimdva | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  →  ( ∀ 𝑥  ∈  𝑜 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  →  ∀ 𝑥  ∈  𝑜 ( ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) ) | 
						
							| 63 | 40 62 | syld | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  →  ( ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  →  ∀ 𝑥  ∈  𝑜 ( ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) ) | 
						
							| 64 | 63 | imp | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  𝑜  ∈  𝒫  𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  ∀ 𝑥  ∈  𝑜 ( ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 65 | 64 | an32s | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  ∧  𝑜  ∈  𝒫  𝑋 )  →  ∀ 𝑥  ∈  𝑜 ( ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 66 |  | ralbi | ⊢ ( ∀ 𝑥  ∈  𝑜 ( ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ )  →  ( ∀ 𝑥  ∈  𝑜 ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ∀ 𝑥  ∈  𝑜 ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 67 | 65 66 | syl | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  ∧  𝑜  ∈  𝒫  𝑋 )  →  ( ∀ 𝑥  ∈  𝑜 ∃ 𝑧  ∈  𝑗 ( 𝑥  ∈  𝑧  ∧  𝑧  ⊆  𝑜 )  ↔  ∀ 𝑥  ∈  𝑜 ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 68 | 36 67 | bitrd | ⊢ ( ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  ∧  𝑜  ∈  𝒫  𝑋 )  →  ( 𝑜  ∈  𝑗  ↔  ∀ 𝑥  ∈  𝑜 ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ ) ) | 
						
							| 69 | 68 | rabbi2dva | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  ( 𝒫  𝑋  ∩  𝑗 )  =  { 𝑜  ∈  𝒫  𝑋  ∣  ∀ 𝑥  ∈  𝑜 ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑜 )  ≠  ∅ } ) | 
						
							| 70 | 69 4 | eqtr4di | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  ( 𝒫  𝑋  ∩  𝑗 )  =  𝐽 ) | 
						
							| 71 | 32 70 | eqtr3d | ⊢ ( ( ( 𝜑  ∧  𝑗  ∈  ( TopOn ‘ 𝑋 ) )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  𝑗  =  𝐽 ) | 
						
							| 72 | 71 | expl | ⊢ ( 𝜑  →  ( ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  𝑗  =  𝐽 ) ) | 
						
							| 73 | 72 | alrimiv | ⊢ ( 𝜑  →  ∀ 𝑗 ( ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  𝑗  =  𝐽 ) ) | 
						
							| 74 |  | eleq1 | ⊢ ( 𝑗  =  𝐽  →  ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ↔  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) ) | 
						
							| 75 |  | fveq2 | ⊢ ( 𝑗  =  𝐽  →  ( nei ‘ 𝑗 )  =  ( nei ‘ 𝐽 ) ) | 
						
							| 76 | 75 | fveq1d | ⊢ ( 𝑗  =  𝐽  →  ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } ) ) | 
						
							| 77 | 76 | eqeq1d | ⊢ ( 𝑗  =  𝐽  →  ( ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  ↔  ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 78 | 77 | ralbidv | ⊢ ( 𝑗  =  𝐽  →  ( ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  ↔  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 79 | 74 78 | anbi12d | ⊢ ( 𝑗  =  𝐽  →  ( ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  ↔  ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) ) | 
						
							| 80 | 79 | eqeu | ⊢ ( ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝐽 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  ∧  ∀ 𝑗 ( ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } )  →  𝑗  =  𝐽 ) )  →  ∃! 𝑗 ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 81 | 7 7 24 73 80 | syl121anc | ⊢ ( 𝜑  →  ∃! 𝑗 ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 82 |  | df-reu | ⊢ ( ∃! 𝑗  ∈  ( TopOn ‘ 𝑋 ) ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ }  ↔  ∃! 𝑗 ( 𝑗  ∈  ( TopOn ‘ 𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) ) | 
						
							| 83 | 81 82 | sylibr | ⊢ ( 𝜑  →  ∃! 𝑗  ∈  ( TopOn ‘ 𝑋 ) ∀ 𝑥  ∈  𝑋 ( ( nei ‘ 𝑗 ) ‘ { 𝑥 } )  =  { 𝑛  ∈  𝒫  𝑋  ∣  ( ( 𝐹 ‘ 𝑥 )  ∩  𝒫  𝑛 )  ≠  ∅ } ) |