| Step | Hyp | Ref | Expression | 
						
							| 1 |  | tgpcn.j | ⊢ 𝐽  =  ( TopOpen ‘ 𝐺 ) | 
						
							| 2 |  | cnmpt1plusg.p | ⊢  +   =  ( +g ‘ 𝐺 ) | 
						
							| 3 |  | cnmpt1plusg.g | ⊢ ( 𝜑  →  𝐺  ∈  TopMnd ) | 
						
							| 4 |  | cnmpt1plusg.k | ⊢ ( 𝜑  →  𝐾  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 5 |  | cnmpt2plusg.l | ⊢ ( 𝜑  →  𝐿  ∈  ( TopOn ‘ 𝑌 ) ) | 
						
							| 6 |  | cnmpt2plusg.a | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐴 )  ∈  ( ( 𝐾  ×t  𝐿 )  Cn  𝐽 ) ) | 
						
							| 7 |  | cnmpt2plusg.b | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐵 )  ∈  ( ( 𝐾  ×t  𝐿 )  Cn  𝐽 ) ) | 
						
							| 8 |  | txtopon | ⊢ ( ( 𝐾  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐿  ∈  ( TopOn ‘ 𝑌 ) )  →  ( 𝐾  ×t  𝐿 )  ∈  ( TopOn ‘ ( 𝑋  ×  𝑌 ) ) ) | 
						
							| 9 | 4 5 8 | syl2anc | ⊢ ( 𝜑  →  ( 𝐾  ×t  𝐿 )  ∈  ( TopOn ‘ ( 𝑋  ×  𝑌 ) ) ) | 
						
							| 10 |  | eqid | ⊢ ( Base ‘ 𝐺 )  =  ( Base ‘ 𝐺 ) | 
						
							| 11 | 1 10 | tmdtopon | ⊢ ( 𝐺  ∈  TopMnd  →  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) ) ) | 
						
							| 12 | 3 11 | syl | ⊢ ( 𝜑  →  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) ) ) | 
						
							| 13 |  | cnf2 | ⊢ ( ( ( 𝐾  ×t  𝐿 )  ∈  ( TopOn ‘ ( 𝑋  ×  𝑌 ) )  ∧  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) )  ∧  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐴 )  ∈  ( ( 𝐾  ×t  𝐿 )  Cn  𝐽 ) )  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐴 ) : ( 𝑋  ×  𝑌 ) ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 14 | 9 12 6 13 | syl3anc | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐴 ) : ( 𝑋  ×  𝑌 ) ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 15 |  | eqid | ⊢ ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐴 )  =  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐴 ) | 
						
							| 16 | 15 | fmpo | ⊢ ( ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑌 𝐴  ∈  ( Base ‘ 𝐺 )  ↔  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐴 ) : ( 𝑋  ×  𝑌 ) ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 17 | 14 16 | sylibr | ⊢ ( 𝜑  →  ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑌 𝐴  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 18 | 17 | r19.21bi | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  →  ∀ 𝑦  ∈  𝑌 𝐴  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 19 | 18 | r19.21bi | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  ∧  𝑦  ∈  𝑌 )  →  𝐴  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 20 | 19 | 3impa | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋  ∧  𝑦  ∈  𝑌 )  →  𝐴  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 21 |  | cnf2 | ⊢ ( ( ( 𝐾  ×t  𝐿 )  ∈  ( TopOn ‘ ( 𝑋  ×  𝑌 ) )  ∧  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) )  ∧  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐵 )  ∈  ( ( 𝐾  ×t  𝐿 )  Cn  𝐽 ) )  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐵 ) : ( 𝑋  ×  𝑌 ) ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 22 | 9 12 7 21 | syl3anc | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐵 ) : ( 𝑋  ×  𝑌 ) ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 23 |  | eqid | ⊢ ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐵 )  =  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐵 ) | 
						
							| 24 | 23 | fmpo | ⊢ ( ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑌 𝐵  ∈  ( Base ‘ 𝐺 )  ↔  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  𝐵 ) : ( 𝑋  ×  𝑌 ) ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 25 | 22 24 | sylibr | ⊢ ( 𝜑  →  ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑌 𝐵  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 26 | 25 | r19.21bi | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  →  ∀ 𝑦  ∈  𝑌 𝐵  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 27 | 26 | r19.21bi | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  ∧  𝑦  ∈  𝑌 )  →  𝐵  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 28 | 27 | 3impa | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋  ∧  𝑦  ∈  𝑌 )  →  𝐵  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 29 |  | eqid | ⊢ ( +𝑓 ‘ 𝐺 )  =  ( +𝑓 ‘ 𝐺 ) | 
						
							| 30 | 10 2 29 | plusfval | ⊢ ( ( 𝐴  ∈  ( Base ‘ 𝐺 )  ∧  𝐵  ∈  ( Base ‘ 𝐺 ) )  →  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 )  =  ( 𝐴  +  𝐵 ) ) | 
						
							| 31 | 20 28 30 | syl2anc | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋  ∧  𝑦  ∈  𝑌 )  →  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 )  =  ( 𝐴  +  𝐵 ) ) | 
						
							| 32 | 31 | mpoeq3dva | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 ) )  =  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  ( 𝐴  +  𝐵 ) ) ) | 
						
							| 33 | 1 29 | tmdcn | ⊢ ( 𝐺  ∈  TopMnd  →  ( +𝑓 ‘ 𝐺 )  ∈  ( ( 𝐽  ×t  𝐽 )  Cn  𝐽 ) ) | 
						
							| 34 | 3 33 | syl | ⊢ ( 𝜑  →  ( +𝑓 ‘ 𝐺 )  ∈  ( ( 𝐽  ×t  𝐽 )  Cn  𝐽 ) ) | 
						
							| 35 | 4 5 6 7 34 | cnmpt22f | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 ) )  ∈  ( ( 𝐾  ×t  𝐿 )  Cn  𝐽 ) ) | 
						
							| 36 | 32 35 | eqeltrrd | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋 ,  𝑦  ∈  𝑌  ↦  ( 𝐴  +  𝐵 ) )  ∈  ( ( 𝐾  ×t  𝐿 )  Cn  𝐽 ) ) |