| Step | Hyp | Ref | Expression | 
						
							| 1 |  | imastps.u | ⊢ ( 𝜑  →  𝑈  =  ( 𝐹  “s  𝑅 ) ) | 
						
							| 2 |  | imastps.v | ⊢ ( 𝜑  →  𝑉  =  ( Base ‘ 𝑅 ) ) | 
						
							| 3 |  | imastps.f | ⊢ ( 𝜑  →  𝐹 : 𝑉 –onto→ 𝐵 ) | 
						
							| 4 |  | imastopn.r | ⊢ ( 𝜑  →  𝑅  ∈  𝑊 ) | 
						
							| 5 |  | imastopn.j | ⊢ 𝐽  =  ( TopOpen ‘ 𝑅 ) | 
						
							| 6 |  | imastopn.o | ⊢ 𝑂  =  ( TopOpen ‘ 𝑈 ) | 
						
							| 7 |  | eqid | ⊢ ( TopSet ‘ 𝑈 )  =  ( TopSet ‘ 𝑈 ) | 
						
							| 8 | 1 2 3 4 5 7 | imastset | ⊢ ( 𝜑  →  ( TopSet ‘ 𝑈 )  =  ( 𝐽  qTop  𝐹 ) ) | 
						
							| 9 | 5 | fvexi | ⊢ 𝐽  ∈  V | 
						
							| 10 |  | fofn | ⊢ ( 𝐹 : 𝑉 –onto→ 𝐵  →  𝐹  Fn  𝑉 ) | 
						
							| 11 | 3 10 | syl | ⊢ ( 𝜑  →  𝐹  Fn  𝑉 ) | 
						
							| 12 |  | fvex | ⊢ ( Base ‘ 𝑅 )  ∈  V | 
						
							| 13 | 2 12 | eqeltrdi | ⊢ ( 𝜑  →  𝑉  ∈  V ) | 
						
							| 14 |  | fnex | ⊢ ( ( 𝐹  Fn  𝑉  ∧  𝑉  ∈  V )  →  𝐹  ∈  V ) | 
						
							| 15 | 11 13 14 | syl2anc | ⊢ ( 𝜑  →  𝐹  ∈  V ) | 
						
							| 16 |  | eqid | ⊢ ∪  𝐽  =  ∪  𝐽 | 
						
							| 17 | 16 | qtopval | ⊢ ( ( 𝐽  ∈  V  ∧  𝐹  ∈  V )  →  ( 𝐽  qTop  𝐹 )  =  { 𝑥  ∈  𝒫  ( 𝐹  “  ∪  𝐽 )  ∣  ( ( ◡ 𝐹  “  𝑥 )  ∩  ∪  𝐽 )  ∈  𝐽 } ) | 
						
							| 18 | 9 15 17 | sylancr | ⊢ ( 𝜑  →  ( 𝐽  qTop  𝐹 )  =  { 𝑥  ∈  𝒫  ( 𝐹  “  ∪  𝐽 )  ∣  ( ( ◡ 𝐹  “  𝑥 )  ∩  ∪  𝐽 )  ∈  𝐽 } ) | 
						
							| 19 | 8 18 | eqtrd | ⊢ ( 𝜑  →  ( TopSet ‘ 𝑈 )  =  { 𝑥  ∈  𝒫  ( 𝐹  “  ∪  𝐽 )  ∣  ( ( ◡ 𝐹  “  𝑥 )  ∩  ∪  𝐽 )  ∈  𝐽 } ) | 
						
							| 20 |  | ssrab2 | ⊢ { 𝑥  ∈  𝒫  ( 𝐹  “  ∪  𝐽 )  ∣  ( ( ◡ 𝐹  “  𝑥 )  ∩  ∪  𝐽 )  ∈  𝐽 }  ⊆  𝒫  ( 𝐹  “  ∪  𝐽 ) | 
						
							| 21 |  | imassrn | ⊢ ( 𝐹  “  ∪  𝐽 )  ⊆  ran  𝐹 | 
						
							| 22 |  | forn | ⊢ ( 𝐹 : 𝑉 –onto→ 𝐵  →  ran  𝐹  =  𝐵 ) | 
						
							| 23 | 3 22 | syl | ⊢ ( 𝜑  →  ran  𝐹  =  𝐵 ) | 
						
							| 24 | 1 2 3 4 | imasbas | ⊢ ( 𝜑  →  𝐵  =  ( Base ‘ 𝑈 ) ) | 
						
							| 25 | 23 24 | eqtrd | ⊢ ( 𝜑  →  ran  𝐹  =  ( Base ‘ 𝑈 ) ) | 
						
							| 26 | 21 25 | sseqtrid | ⊢ ( 𝜑  →  ( 𝐹  “  ∪  𝐽 )  ⊆  ( Base ‘ 𝑈 ) ) | 
						
							| 27 | 26 | sspwd | ⊢ ( 𝜑  →  𝒫  ( 𝐹  “  ∪  𝐽 )  ⊆  𝒫  ( Base ‘ 𝑈 ) ) | 
						
							| 28 | 20 27 | sstrid | ⊢ ( 𝜑  →  { 𝑥  ∈  𝒫  ( 𝐹  “  ∪  𝐽 )  ∣  ( ( ◡ 𝐹  “  𝑥 )  ∩  ∪  𝐽 )  ∈  𝐽 }  ⊆  𝒫  ( Base ‘ 𝑈 ) ) | 
						
							| 29 | 19 28 | eqsstrd | ⊢ ( 𝜑  →  ( TopSet ‘ 𝑈 )  ⊆  𝒫  ( Base ‘ 𝑈 ) ) | 
						
							| 30 |  | eqid | ⊢ ( Base ‘ 𝑈 )  =  ( Base ‘ 𝑈 ) | 
						
							| 31 | 30 7 | topnid | ⊢ ( ( TopSet ‘ 𝑈 )  ⊆  𝒫  ( Base ‘ 𝑈 )  →  ( TopSet ‘ 𝑈 )  =  ( TopOpen ‘ 𝑈 ) ) | 
						
							| 32 | 29 31 | syl | ⊢ ( 𝜑  →  ( TopSet ‘ 𝑈 )  =  ( TopOpen ‘ 𝑈 ) ) | 
						
							| 33 | 32 6 | eqtr4di | ⊢ ( 𝜑  →  ( TopSet ‘ 𝑈 )  =  𝑂 ) | 
						
							| 34 | 33 8 | eqtr3d | ⊢ ( 𝜑  →  𝑂  =  ( 𝐽  qTop  𝐹 ) ) |