| Step | Hyp | Ref | Expression | 
						
							| 1 |  | gsumpropd2.f | ⊢ ( 𝜑  →  𝐹  ∈  𝑉 ) | 
						
							| 2 |  | gsumpropd2.g | ⊢ ( 𝜑  →  𝐺  ∈  𝑊 ) | 
						
							| 3 |  | gsumpropd2.h | ⊢ ( 𝜑  →  𝐻  ∈  𝑋 ) | 
						
							| 4 |  | gsumpropd2.b | ⊢ ( 𝜑  →  ( Base ‘ 𝐺 )  =  ( Base ‘ 𝐻 ) ) | 
						
							| 5 |  | gsumpropd2.c | ⊢ ( ( 𝜑  ∧  ( 𝑠  ∈  ( Base ‘ 𝐺 )  ∧  𝑡  ∈  ( Base ‘ 𝐺 ) ) )  →  ( 𝑠 ( +g ‘ 𝐺 ) 𝑡 )  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 6 |  | gsumpropd2.e | ⊢ ( ( 𝜑  ∧  ( 𝑠  ∈  ( Base ‘ 𝐺 )  ∧  𝑡  ∈  ( Base ‘ 𝐺 ) ) )  →  ( 𝑠 ( +g ‘ 𝐺 ) 𝑡 )  =  ( 𝑠 ( +g ‘ 𝐻 ) 𝑡 ) ) | 
						
							| 7 |  | gsumpropd2.n | ⊢ ( 𝜑  →  Fun  𝐹 ) | 
						
							| 8 |  | gsumpropd2.r | ⊢ ( 𝜑  →  ran  𝐹  ⊆  ( Base ‘ 𝐺 ) ) | 
						
							| 9 |  | eqid | ⊢ ( ◡ 𝐹  “  ( V  ∖  { 𝑠  ∈  ( Base ‘ 𝐺 )  ∣  ∀ 𝑡  ∈  ( Base ‘ 𝐺 ) ( ( 𝑠 ( +g ‘ 𝐺 ) 𝑡 )  =  𝑡  ∧  ( 𝑡 ( +g ‘ 𝐺 ) 𝑠 )  =  𝑡 ) } ) )  =  ( ◡ 𝐹  “  ( V  ∖  { 𝑠  ∈  ( Base ‘ 𝐺 )  ∣  ∀ 𝑡  ∈  ( Base ‘ 𝐺 ) ( ( 𝑠 ( +g ‘ 𝐺 ) 𝑡 )  =  𝑡  ∧  ( 𝑡 ( +g ‘ 𝐺 ) 𝑠 )  =  𝑡 ) } ) ) | 
						
							| 10 |  | eqid | ⊢ ( ◡ 𝐹  “  ( V  ∖  { 𝑠  ∈  ( Base ‘ 𝐻 )  ∣  ∀ 𝑡  ∈  ( Base ‘ 𝐻 ) ( ( 𝑠 ( +g ‘ 𝐻 ) 𝑡 )  =  𝑡  ∧  ( 𝑡 ( +g ‘ 𝐻 ) 𝑠 )  =  𝑡 ) } ) )  =  ( ◡ 𝐹  “  ( V  ∖  { 𝑠  ∈  ( Base ‘ 𝐻 )  ∣  ∀ 𝑡  ∈  ( Base ‘ 𝐻 ) ( ( 𝑠 ( +g ‘ 𝐻 ) 𝑡 )  =  𝑡  ∧  ( 𝑡 ( +g ‘ 𝐻 ) 𝑠 )  =  𝑡 ) } ) ) | 
						
							| 11 | 1 2 3 4 5 6 7 8 9 10 | gsumpropd2lem | ⊢ ( 𝜑  →  ( 𝐺  Σg  𝐹 )  =  ( 𝐻  Σg  𝐹 ) ) |