| Step | Hyp | Ref | Expression | 
						
							| 1 |  | txlly.1 | ⊢ ( ( 𝑗  ∈  𝐴  ∧  𝑘  ∈  𝐴 )  →  ( 𝑗  ×t  𝑘 )  ∈  𝐴 ) | 
						
							| 2 |  | llytop | ⊢ ( 𝑅  ∈  Locally  𝐴  →  𝑅  ∈  Top ) | 
						
							| 3 |  | llytop | ⊢ ( 𝑆  ∈  Locally  𝐴  →  𝑆  ∈  Top ) | 
						
							| 4 |  | txtop | ⊢ ( ( 𝑅  ∈  Top  ∧  𝑆  ∈  Top )  →  ( 𝑅  ×t  𝑆 )  ∈  Top ) | 
						
							| 5 | 2 3 4 | syl2an | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  →  ( 𝑅  ×t  𝑆 )  ∈  Top ) | 
						
							| 6 |  | eltx | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  →  ( 𝑥  ∈  ( 𝑅  ×t  𝑆 )  ↔  ∀ 𝑦  ∈  𝑥 ∃ 𝑢  ∈  𝑅 ∃ 𝑣  ∈  𝑆 ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) ) | 
						
							| 7 |  | simpll | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  𝑅  ∈  Locally  𝐴 ) | 
						
							| 8 |  | simprll | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  𝑢  ∈  𝑅 ) | 
						
							| 9 |  | simprrl | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  𝑦  ∈  ( 𝑢  ×  𝑣 ) ) | 
						
							| 10 |  | xp1st | ⊢ ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  →  ( 1st  ‘ 𝑦 )  ∈  𝑢 ) | 
						
							| 11 | 9 10 | syl | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ( 1st  ‘ 𝑦 )  ∈  𝑢 ) | 
						
							| 12 |  | llyi | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑢  ∈  𝑅  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑢 )  →  ∃ 𝑟  ∈  𝑅 ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 ) ) | 
						
							| 13 | 7 8 11 12 | syl3anc | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ∃ 𝑟  ∈  𝑅 ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 ) ) | 
						
							| 14 |  | simplr | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  𝑆  ∈  Locally  𝐴 ) | 
						
							| 15 |  | simprlr | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  𝑣  ∈  𝑆 ) | 
						
							| 16 |  | xp2nd | ⊢ ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  →  ( 2nd  ‘ 𝑦 )  ∈  𝑣 ) | 
						
							| 17 | 9 16 | syl | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ( 2nd  ‘ 𝑦 )  ∈  𝑣 ) | 
						
							| 18 |  | llyi | ⊢ ( ( 𝑆  ∈  Locally  𝐴  ∧  𝑣  ∈  𝑆  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑣 )  →  ∃ 𝑠  ∈  𝑆 ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) | 
						
							| 19 | 14 15 17 18 | syl3anc | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ∃ 𝑠  ∈  𝑆 ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) | 
						
							| 20 |  | reeanv | ⊢ ( ∃ 𝑟  ∈  𝑅 ∃ 𝑠  ∈  𝑆 ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) )  ↔  ( ∃ 𝑟  ∈  𝑅 ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ∃ 𝑠  ∈  𝑆 ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) | 
						
							| 21 | 2 | ad3antrrr | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  𝑅  ∈  Top ) | 
						
							| 22 | 3 | ad3antlr | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  𝑆  ∈  Top ) | 
						
							| 23 |  | simprll | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  𝑟  ∈  𝑅 ) | 
						
							| 24 |  | simprlr | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  𝑠  ∈  𝑆 ) | 
						
							| 25 |  | txopn | ⊢ ( ( ( 𝑅  ∈  Top  ∧  𝑆  ∈  Top )  ∧  ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 ) )  →  ( 𝑟  ×  𝑠 )  ∈  ( 𝑅  ×t  𝑆 ) ) | 
						
							| 26 | 21 22 23 24 25 | syl22anc | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ( 𝑟  ×  𝑠 )  ∈  ( 𝑅  ×t  𝑆 ) ) | 
						
							| 27 |  | simprl1 | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  𝑟  ⊆  𝑢 ) | 
						
							| 28 |  | simprr1 | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  𝑠  ⊆  𝑣 ) | 
						
							| 29 |  | xpss12 | ⊢ ( ( 𝑟  ⊆  𝑢  ∧  𝑠  ⊆  𝑣 )  →  ( 𝑟  ×  𝑠 )  ⊆  ( 𝑢  ×  𝑣 ) ) | 
						
							| 30 | 27 28 29 | syl2anc | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  ( 𝑟  ×  𝑠 )  ⊆  ( 𝑢  ×  𝑣 ) ) | 
						
							| 31 |  | simprrr | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) | 
						
							| 32 | 30 31 | sylan9ssr | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ( 𝑟  ×  𝑠 )  ⊆  𝑥 ) | 
						
							| 33 |  | vex | ⊢ 𝑥  ∈  V | 
						
							| 34 | 33 | elpw2 | ⊢ ( ( 𝑟  ×  𝑠 )  ∈  𝒫  𝑥  ↔  ( 𝑟  ×  𝑠 )  ⊆  𝑥 ) | 
						
							| 35 | 32 34 | sylibr | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ( 𝑟  ×  𝑠 )  ∈  𝒫  𝑥 ) | 
						
							| 36 | 26 35 | elind | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ( 𝑟  ×  𝑠 )  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ) | 
						
							| 37 |  | 1st2nd2 | ⊢ ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  →  𝑦  =  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉 ) | 
						
							| 38 | 9 37 | syl | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  𝑦  =  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉 ) | 
						
							| 39 | 38 | adantr | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  𝑦  =  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉 ) | 
						
							| 40 |  | simprl2 | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  ( 1st  ‘ 𝑦 )  ∈  𝑟 ) | 
						
							| 41 |  | simprr2 | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  ( 2nd  ‘ 𝑦 )  ∈  𝑠 ) | 
						
							| 42 | 40 41 | opelxpd | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉  ∈  ( 𝑟  ×  𝑠 ) ) | 
						
							| 43 | 42 | adantl | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉  ∈  ( 𝑟  ×  𝑠 ) ) | 
						
							| 44 | 39 43 | eqeltrd | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  𝑦  ∈  ( 𝑟  ×  𝑠 ) ) | 
						
							| 45 |  | txrest | ⊢ ( ( ( 𝑅  ∈  Top  ∧  𝑆  ∈  Top )  ∧  ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 ) )  →  ( ( 𝑅  ×t  𝑆 )  ↾t  ( 𝑟  ×  𝑠 ) )  =  ( ( 𝑅  ↾t  𝑟 )  ×t  ( 𝑆  ↾t  𝑠 ) ) ) | 
						
							| 46 | 21 22 23 24 45 | syl22anc | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ( ( 𝑅  ×t  𝑆 )  ↾t  ( 𝑟  ×  𝑠 ) )  =  ( ( 𝑅  ↾t  𝑟 )  ×t  ( 𝑆  ↾t  𝑠 ) ) ) | 
						
							| 47 |  | simprl3 | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 ) | 
						
							| 48 |  | simprr3 | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) | 
						
							| 49 | 1 | caovcl | ⊢ ( ( ( 𝑅  ↾t  𝑟 )  ∈  𝐴  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 )  →  ( ( 𝑅  ↾t  𝑟 )  ×t  ( 𝑆  ↾t  𝑠 ) )  ∈  𝐴 ) | 
						
							| 50 | 47 48 49 | syl2anc | ⊢ ( ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) )  →  ( ( 𝑅  ↾t  𝑟 )  ×t  ( 𝑆  ↾t  𝑠 ) )  ∈  𝐴 ) | 
						
							| 51 | 50 | adantl | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ( ( 𝑅  ↾t  𝑟 )  ×t  ( 𝑆  ↾t  𝑠 ) )  ∈  𝐴 ) | 
						
							| 52 | 46 51 | eqeltrd | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ( ( 𝑅  ×t  𝑆 )  ↾t  ( 𝑟  ×  𝑠 ) )  ∈  𝐴 ) | 
						
							| 53 |  | eleq2 | ⊢ ( 𝑧  =  ( 𝑟  ×  𝑠 )  →  ( 𝑦  ∈  𝑧  ↔  𝑦  ∈  ( 𝑟  ×  𝑠 ) ) ) | 
						
							| 54 |  | oveq2 | ⊢ ( 𝑧  =  ( 𝑟  ×  𝑠 )  →  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  =  ( ( 𝑅  ×t  𝑆 )  ↾t  ( 𝑟  ×  𝑠 ) ) ) | 
						
							| 55 | 54 | eleq1d | ⊢ ( 𝑧  =  ( 𝑟  ×  𝑠 )  →  ( ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴  ↔  ( ( 𝑅  ×t  𝑆 )  ↾t  ( 𝑟  ×  𝑠 ) )  ∈  𝐴 ) ) | 
						
							| 56 | 53 55 | anbi12d | ⊢ ( 𝑧  =  ( 𝑟  ×  𝑠 )  →  ( ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 )  ↔  ( 𝑦  ∈  ( 𝑟  ×  𝑠 )  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  ( 𝑟  ×  𝑠 ) )  ∈  𝐴 ) ) ) | 
						
							| 57 | 56 | rspcev | ⊢ ( ( ( 𝑟  ×  𝑠 )  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 )  ∧  ( 𝑦  ∈  ( 𝑟  ×  𝑠 )  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  ( 𝑟  ×  𝑠 ) )  ∈  𝐴 ) )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) | 
						
							| 58 | 36 44 52 57 | syl12anc | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 )  ∧  ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) ) ) )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) | 
						
							| 59 | 58 | expr | ⊢ ( ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  ∧  ( 𝑟  ∈  𝑅  ∧  𝑠  ∈  𝑆 ) )  →  ( ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 60 | 59 | rexlimdvva | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ( ∃ 𝑟  ∈  𝑅 ∃ 𝑠  ∈  𝑆 ( ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 61 | 20 60 | biimtrrid | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ( ( ∃ 𝑟  ∈  𝑅 ( 𝑟  ⊆  𝑢  ∧  ( 1st  ‘ 𝑦 )  ∈  𝑟  ∧  ( 𝑅  ↾t  𝑟 )  ∈  𝐴 )  ∧  ∃ 𝑠  ∈  𝑆 ( 𝑠  ⊆  𝑣  ∧  ( 2nd  ‘ 𝑦 )  ∈  𝑠  ∧  ( 𝑆  ↾t  𝑠 )  ∈  𝐴 ) )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 62 | 13 19 61 | mp2and | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 )  ∧  ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 ) ) )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) | 
						
							| 63 | 62 | expr | ⊢ ( ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  ∧  ( 𝑢  ∈  𝑅  ∧  𝑣  ∈  𝑆 ) )  →  ( ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 64 | 63 | rexlimdvva | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  →  ( ∃ 𝑢  ∈  𝑅 ∃ 𝑣  ∈  𝑆 ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 )  →  ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 65 | 64 | ralimdv | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  →  ( ∀ 𝑦  ∈  𝑥 ∃ 𝑢  ∈  𝑅 ∃ 𝑣  ∈  𝑆 ( 𝑦  ∈  ( 𝑢  ×  𝑣 )  ∧  ( 𝑢  ×  𝑣 )  ⊆  𝑥 )  →  ∀ 𝑦  ∈  𝑥 ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 66 | 6 65 | sylbid | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  →  ( 𝑥  ∈  ( 𝑅  ×t  𝑆 )  →  ∀ 𝑦  ∈  𝑥 ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 67 | 66 | ralrimiv | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  →  ∀ 𝑥  ∈  ( 𝑅  ×t  𝑆 ) ∀ 𝑦  ∈  𝑥 ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) | 
						
							| 68 |  | islly | ⊢ ( ( 𝑅  ×t  𝑆 )  ∈  Locally  𝐴  ↔  ( ( 𝑅  ×t  𝑆 )  ∈  Top  ∧  ∀ 𝑥  ∈  ( 𝑅  ×t  𝑆 ) ∀ 𝑦  ∈  𝑥 ∃ 𝑧  ∈  ( ( 𝑅  ×t  𝑆 )  ∩  𝒫  𝑥 ) ( 𝑦  ∈  𝑧  ∧  ( ( 𝑅  ×t  𝑆 )  ↾t  𝑧 )  ∈  𝐴 ) ) ) | 
						
							| 69 | 5 67 68 | sylanbrc | ⊢ ( ( 𝑅  ∈  Locally  𝐴  ∧  𝑆  ∈  Locally  𝐴 )  →  ( 𝑅  ×t  𝑆 )  ∈  Locally  𝐴 ) |