| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mnringmulrd.1 | ⊢ 𝐹  =  ( 𝑅  MndRing  𝑀 ) | 
						
							| 2 |  | mnringmulrd.2 | ⊢ 𝐵  =  ( Base ‘ 𝐹 ) | 
						
							| 3 |  | mnringmulrd.3 | ⊢  ·   =  ( .r ‘ 𝑅 ) | 
						
							| 4 |  | mnringmulrd.4 | ⊢  0   =  ( 0g ‘ 𝑅 ) | 
						
							| 5 |  | mnringmulrd.5 | ⊢ 𝐴  =  ( Base ‘ 𝑀 ) | 
						
							| 6 |  | mnringmulrd.6 | ⊢  +   =  ( +g ‘ 𝑀 ) | 
						
							| 7 |  | mnringmulrd.7 | ⊢ ( 𝜑  →  𝑅  ∈  𝑈 ) | 
						
							| 8 |  | mnringmulrd.8 | ⊢ ( 𝜑  →  𝑀  ∈  𝑊 ) | 
						
							| 9 |  | eqid | ⊢ ( 𝑅  freeLMod  𝐴 )  =  ( 𝑅  freeLMod  𝐴 ) | 
						
							| 10 | 1 2 5 9 7 8 | mnringbaserd | ⊢ ( 𝜑  →  𝐵  =  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ) | 
						
							| 11 | 5 | fvexi | ⊢ 𝐴  ∈  V | 
						
							| 12 | 11 11 | mpoex | ⊢ ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) )  ∈  V | 
						
							| 13 | 12 | a1i | ⊢ ( 𝜑  →  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) )  ∈  V ) | 
						
							| 14 | 1 | ovexi | ⊢ 𝐹  ∈  V | 
						
							| 15 | 14 | a1i | ⊢ ( 𝜑  →  𝐹  ∈  V ) | 
						
							| 16 |  | ovex | ⊢ ( 𝑅  freeLMod  𝐴 )  ∈  V | 
						
							| 17 | 16 | a1i | ⊢ ( 𝜑  →  ( 𝑅  freeLMod  𝐴 )  ∈  V ) | 
						
							| 18 | 2 10 | eqtr3id | ⊢ ( 𝜑  →  ( Base ‘ 𝐹 )  =  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ) | 
						
							| 19 | 1 5 9 7 8 | mnringaddgd | ⊢ ( 𝜑  →  ( +g ‘ ( 𝑅  freeLMod  𝐴 ) )  =  ( +g ‘ 𝐹 ) ) | 
						
							| 20 | 19 | eqcomd | ⊢ ( 𝜑  →  ( +g ‘ 𝐹 )  =  ( +g ‘ ( 𝑅  freeLMod  𝐴 ) ) ) | 
						
							| 21 | 13 15 17 18 20 | gsumpropd | ⊢ ( 𝜑  →  ( 𝐹  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) )  =  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) ) | 
						
							| 22 | 10 10 21 | mpoeq123dv | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝐵 ,  𝑦  ∈  𝐵  ↦  ( 𝐹  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) )  =  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) ) ) | 
						
							| 23 |  | fvex | ⊢ ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ∈  V | 
						
							| 24 | 23 23 | mpoex | ⊢ ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) )  ∈  V | 
						
							| 25 |  | mulridx | ⊢ .r  =  Slot  ( .r ‘ ndx ) | 
						
							| 26 | 25 | setsid | ⊢ ( ( ( 𝑅  freeLMod  𝐴 )  ∈  V  ∧  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) )  ∈  V )  →  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) )  =  ( .r ‘ ( ( 𝑅  freeLMod  𝐴 )  sSet  〈 ( .r ‘ ndx ) ,  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) ) 〉 ) ) ) | 
						
							| 27 | 16 24 26 | mp2an | ⊢ ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) )  =  ( .r ‘ ( ( 𝑅  freeLMod  𝐴 )  sSet  〈 ( .r ‘ ndx ) ,  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) ) 〉 ) ) | 
						
							| 28 |  | eqid | ⊢ ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  =  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) | 
						
							| 29 | 1 3 4 5 6 9 28 7 8 | mnringvald | ⊢ ( 𝜑  →  𝐹  =  ( ( 𝑅  freeLMod  𝐴 )  sSet  〈 ( .r ‘ ndx ) ,  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) ) 〉 ) ) | 
						
							| 30 | 29 | fveq2d | ⊢ ( 𝜑  →  ( .r ‘ 𝐹 )  =  ( .r ‘ ( ( 𝑅  freeLMod  𝐴 )  sSet  〈 ( .r ‘ ndx ) ,  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) ) 〉 ) ) ) | 
						
							| 31 | 27 30 | eqtr4id | ⊢ ( 𝜑  →  ( 𝑥  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) ) ,  𝑦  ∈  ( Base ‘ ( 𝑅  freeLMod  𝐴 ) )  ↦  ( ( 𝑅  freeLMod  𝐴 )  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) )  =  ( .r ‘ 𝐹 ) ) | 
						
							| 32 | 22 31 | eqtrd | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝐵 ,  𝑦  ∈  𝐵  ↦  ( 𝐹  Σg  ( 𝑎  ∈  𝐴 ,  𝑏  ∈  𝐴  ↦  ( 𝑖  ∈  𝐴  ↦  if ( 𝑖  =  ( 𝑎  +  𝑏 ) ,  ( ( 𝑥 ‘ 𝑎 )  ·  ( 𝑦 ‘ 𝑏 ) ) ,   0  ) ) ) ) )  =  ( .r ‘ 𝐹 ) ) |