| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elpi1.g | ⊢ 𝐺  =  ( 𝐽  π1  𝑌 ) | 
						
							| 2 |  | elpi1.b | ⊢ 𝐵  =  ( Base ‘ 𝐺 ) | 
						
							| 3 |  | elpi1.1 | ⊢ ( 𝜑  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 4 |  | elpi1.2 | ⊢ ( 𝜑  →  𝑌  ∈  𝑋 ) | 
						
							| 5 |  | pi1addf.p | ⊢  +   =  ( +g ‘ 𝐺 ) | 
						
							| 6 |  | eqidd | ⊢ ( 𝜑  →  ( ( 𝐽  Ω1  𝑌 )  /s  (  ≃ph ‘ 𝐽 ) )  =  ( ( 𝐽  Ω1  𝑌 )  /s  (  ≃ph ‘ 𝐽 ) ) ) | 
						
							| 7 |  | eqidd | ⊢ ( 𝜑  →  ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  =  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) | 
						
							| 8 |  | fvexd | ⊢ ( 𝜑  →  (  ≃ph ‘ 𝐽 )  ∈  V ) | 
						
							| 9 |  | ovexd | ⊢ ( 𝜑  →  ( 𝐽  Ω1  𝑌 )  ∈  V ) | 
						
							| 10 |  | eqid | ⊢ ( 𝐽  Ω1  𝑌 )  =  ( 𝐽  Ω1  𝑌 ) | 
						
							| 11 | 2 | a1i | ⊢ ( 𝜑  →  𝐵  =  ( Base ‘ 𝐺 ) ) | 
						
							| 12 | 1 3 4 10 11 7 | pi1blem | ⊢ ( 𝜑  →  ( ( (  ≃ph ‘ 𝐽 )  “  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) )  ⊆  ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  ∧  ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  ⊆  ( II  Cn  𝐽 ) ) ) | 
						
							| 13 | 12 | simpld | ⊢ ( 𝜑  →  ( (  ≃ph ‘ 𝐽 )  “  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) )  ⊆  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) | 
						
							| 14 | 6 7 8 9 13 | qusin | ⊢ ( 𝜑  →  ( ( 𝐽  Ω1  𝑌 )  /s  (  ≃ph ‘ 𝐽 ) )  =  ( ( 𝐽  Ω1  𝑌 )  /s  ( (  ≃ph ‘ 𝐽 )  ∩  ( ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  ×  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) ) ) ) | 
						
							| 15 | 1 3 4 10 | pi1val | ⊢ ( 𝜑  →  𝐺  =  ( ( 𝐽  Ω1  𝑌 )  /s  (  ≃ph ‘ 𝐽 ) ) ) | 
						
							| 16 | 1 3 4 10 11 7 | pi1buni | ⊢ ( 𝜑  →  ∪  𝐵  =  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) | 
						
							| 17 | 16 | sqxpeqd | ⊢ ( 𝜑  →  ( ∪  𝐵  ×  ∪  𝐵 )  =  ( ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  ×  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) ) | 
						
							| 18 | 17 | ineq2d | ⊢ ( 𝜑  →  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) )  =  ( (  ≃ph ‘ 𝐽 )  ∩  ( ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  ×  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) ) ) | 
						
							| 19 | 18 | oveq2d | ⊢ ( 𝜑  →  ( ( 𝐽  Ω1  𝑌 )  /s  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) )  =  ( ( 𝐽  Ω1  𝑌 )  /s  ( (  ≃ph ‘ 𝐽 )  ∩  ( ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  ×  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) ) ) ) | 
						
							| 20 | 14 15 19 | 3eqtr4d | ⊢ ( 𝜑  →  𝐺  =  ( ( 𝐽  Ω1  𝑌 )  /s  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) | 
						
							| 21 |  | phtpcer | ⊢ (  ≃ph ‘ 𝐽 )  Er  ( II  Cn  𝐽 ) | 
						
							| 22 | 21 | a1i | ⊢ ( 𝜑  →  (  ≃ph ‘ 𝐽 )  Er  ( II  Cn  𝐽 ) ) | 
						
							| 23 | 12 | simprd | ⊢ ( 𝜑  →  ( Base ‘ ( 𝐽  Ω1  𝑌 ) )  ⊆  ( II  Cn  𝐽 ) ) | 
						
							| 24 | 16 23 | eqsstrd | ⊢ ( 𝜑  →  ∪  𝐵  ⊆  ( II  Cn  𝐽 ) ) | 
						
							| 25 | 22 24 | erinxp | ⊢ ( 𝜑  →  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) )  Er  ∪  𝐵 ) | 
						
							| 26 |  | eqid | ⊢ ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) )  =  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) | 
						
							| 27 |  | eqid | ⊢ ( +g ‘ ( 𝐽  Ω1  𝑌 ) )  =  ( +g ‘ ( 𝐽  Ω1  𝑌 ) ) | 
						
							| 28 | 1 3 4 11 26 10 27 | pi1cpbl | ⊢ ( 𝜑  →  ( ( 𝑎 ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) 𝑐  ∧  𝑏 ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) 𝑑 )  →  ( 𝑎 ( +g ‘ ( 𝐽  Ω1  𝑌 ) ) 𝑏 ) ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ( 𝑐 ( +g ‘ ( 𝐽  Ω1  𝑌 ) ) 𝑑 ) ) ) | 
						
							| 29 | 3 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 30 | 4 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  𝑌  ∈  𝑋 ) | 
						
							| 31 | 10 29 30 | om1plusg | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  ( *𝑝 ‘ 𝐽 )  =  ( +g ‘ ( 𝐽  Ω1  𝑌 ) ) ) | 
						
							| 32 | 31 | oveqd | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  ( 𝑐 ( *𝑝 ‘ 𝐽 ) 𝑑 )  =  ( 𝑐 ( +g ‘ ( 𝐽  Ω1  𝑌 ) ) 𝑑 ) ) | 
						
							| 33 | 16 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  ∪  𝐵  =  ( Base ‘ ( 𝐽  Ω1  𝑌 ) ) ) | 
						
							| 34 |  | simprl | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  𝑐  ∈  ∪  𝐵 ) | 
						
							| 35 |  | simprr | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  𝑑  ∈  ∪  𝐵 ) | 
						
							| 36 | 10 29 30 33 34 35 | om1addcl | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  ( 𝑐 ( *𝑝 ‘ 𝐽 ) 𝑑 )  ∈  ∪  𝐵 ) | 
						
							| 37 | 32 36 | eqeltrrd | ⊢ ( ( 𝜑  ∧  ( 𝑐  ∈  ∪  𝐵  ∧  𝑑  ∈  ∪  𝐵 ) )  →  ( 𝑐 ( +g ‘ ( 𝐽  Ω1  𝑌 ) ) 𝑑 )  ∈  ∪  𝐵 ) | 
						
							| 38 | 20 16 25 9 28 37 27 5 | qusaddf | ⊢ ( 𝜑  →   +  : ( ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) )  ×  ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) ⟶ ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) | 
						
							| 39 | 1 3 4 11 26 | pi1bas3 | ⊢ ( 𝜑  →  𝐵  =  ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) | 
						
							| 40 | 39 | sqxpeqd | ⊢ ( 𝜑  →  ( 𝐵  ×  𝐵 )  =  ( ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) )  ×  ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) ) | 
						
							| 41 | 40 | feq2d | ⊢ ( 𝜑  →  (  +  : ( 𝐵  ×  𝐵 ) ⟶ ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) )  ↔   +  : ( ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) )  ×  ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) ⟶ ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) ) | 
						
							| 42 | 38 41 | mpbird | ⊢ ( 𝜑  →   +  : ( 𝐵  ×  𝐵 ) ⟶ ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) | 
						
							| 43 | 39 | feq3d | ⊢ ( 𝜑  →  (  +  : ( 𝐵  ×  𝐵 ) ⟶ 𝐵  ↔   +  : ( 𝐵  ×  𝐵 ) ⟶ ( ∪  𝐵  /  ( (  ≃ph ‘ 𝐽 )  ∩  ( ∪  𝐵  ×  ∪  𝐵 ) ) ) ) ) | 
						
							| 44 | 42 43 | mpbird | ⊢ ( 𝜑  →   +  : ( 𝐵  ×  𝐵 ) ⟶ 𝐵 ) |