| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mamucl.b | ⊢ 𝐵  =  ( Base ‘ 𝑅 ) | 
						
							| 2 |  | mamucl.r | ⊢ ( 𝜑  →  𝑅  ∈  Ring ) | 
						
							| 3 |  | mamucl.f | ⊢ 𝐹  =  ( 𝑅  maMul  〈 𝑀 ,  𝑁 ,  𝑃 〉 ) | 
						
							| 4 |  | mamucl.m | ⊢ ( 𝜑  →  𝑀  ∈  Fin ) | 
						
							| 5 |  | mamucl.n | ⊢ ( 𝜑  →  𝑁  ∈  Fin ) | 
						
							| 6 |  | mamucl.p | ⊢ ( 𝜑  →  𝑃  ∈  Fin ) | 
						
							| 7 |  | mamucl.x | ⊢ ( 𝜑  →  𝑋  ∈  ( 𝐵  ↑m  ( 𝑀  ×  𝑁 ) ) ) | 
						
							| 8 |  | mamucl.y | ⊢ ( 𝜑  →  𝑌  ∈  ( 𝐵  ↑m  ( 𝑁  ×  𝑃 ) ) ) | 
						
							| 9 |  | eqid | ⊢ ( .r ‘ 𝑅 )  =  ( .r ‘ 𝑅 ) | 
						
							| 10 | 3 1 9 2 4 5 6 7 8 | mamuval | ⊢ ( 𝜑  →  ( 𝑋 𝐹 𝑌 )  =  ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) ) ) | 
						
							| 11 |  | ringcmn | ⊢ ( 𝑅  ∈  Ring  →  𝑅  ∈  CMnd ) | 
						
							| 12 | 2 11 | syl | ⊢ ( 𝜑  →  𝑅  ∈  CMnd ) | 
						
							| 13 | 12 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  →  𝑅  ∈  CMnd ) | 
						
							| 14 | 5 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  →  𝑁  ∈  Fin ) | 
						
							| 15 | 2 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  𝑅  ∈  Ring ) | 
						
							| 16 |  | elmapi | ⊢ ( 𝑋  ∈  ( 𝐵  ↑m  ( 𝑀  ×  𝑁 ) )  →  𝑋 : ( 𝑀  ×  𝑁 ) ⟶ 𝐵 ) | 
						
							| 17 | 7 16 | syl | ⊢ ( 𝜑  →  𝑋 : ( 𝑀  ×  𝑁 ) ⟶ 𝐵 ) | 
						
							| 18 | 17 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  𝑋 : ( 𝑀  ×  𝑁 ) ⟶ 𝐵 ) | 
						
							| 19 |  | simplrl | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  𝑖  ∈  𝑀 ) | 
						
							| 20 |  | simpr | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  𝑗  ∈  𝑁 ) | 
						
							| 21 | 18 19 20 | fovcdmd | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  ( 𝑖 𝑋 𝑗 )  ∈  𝐵 ) | 
						
							| 22 |  | elmapi | ⊢ ( 𝑌  ∈  ( 𝐵  ↑m  ( 𝑁  ×  𝑃 ) )  →  𝑌 : ( 𝑁  ×  𝑃 ) ⟶ 𝐵 ) | 
						
							| 23 | 8 22 | syl | ⊢ ( 𝜑  →  𝑌 : ( 𝑁  ×  𝑃 ) ⟶ 𝐵 ) | 
						
							| 24 | 23 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  𝑌 : ( 𝑁  ×  𝑃 ) ⟶ 𝐵 ) | 
						
							| 25 |  | simplrr | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  𝑘  ∈  𝑃 ) | 
						
							| 26 | 24 20 25 | fovcdmd | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  ( 𝑗 𝑌 𝑘 )  ∈  𝐵 ) | 
						
							| 27 | 1 9 | ringcl | ⊢ ( ( 𝑅  ∈  Ring  ∧  ( 𝑖 𝑋 𝑗 )  ∈  𝐵  ∧  ( 𝑗 𝑌 𝑘 )  ∈  𝐵 )  →  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) )  ∈  𝐵 ) | 
						
							| 28 | 15 21 26 27 | syl3anc | ⊢ ( ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  ∧  𝑗  ∈  𝑁 )  →  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) )  ∈  𝐵 ) | 
						
							| 29 | 28 | ralrimiva | ⊢ ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  →  ∀ 𝑗  ∈  𝑁 ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) )  ∈  𝐵 ) | 
						
							| 30 | 1 13 14 29 | gsummptcl | ⊢ ( ( 𝜑  ∧  ( 𝑖  ∈  𝑀  ∧  𝑘  ∈  𝑃 ) )  →  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) )  ∈  𝐵 ) | 
						
							| 31 | 30 | ralrimivva | ⊢ ( 𝜑  →  ∀ 𝑖  ∈  𝑀 ∀ 𝑘  ∈  𝑃 ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) )  ∈  𝐵 ) | 
						
							| 32 |  | eqid | ⊢ ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) )  =  ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) ) | 
						
							| 33 | 32 | fmpo | ⊢ ( ∀ 𝑖  ∈  𝑀 ∀ 𝑘  ∈  𝑃 ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) )  ∈  𝐵  ↔  ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) ) : ( 𝑀  ×  𝑃 ) ⟶ 𝐵 ) | 
						
							| 34 | 1 | fvexi | ⊢ 𝐵  ∈  V | 
						
							| 35 |  | xpfi | ⊢ ( ( 𝑀  ∈  Fin  ∧  𝑃  ∈  Fin )  →  ( 𝑀  ×  𝑃 )  ∈  Fin ) | 
						
							| 36 | 4 6 35 | syl2anc | ⊢ ( 𝜑  →  ( 𝑀  ×  𝑃 )  ∈  Fin ) | 
						
							| 37 |  | elmapg | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑀  ×  𝑃 )  ∈  Fin )  →  ( ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) )  ∈  ( 𝐵  ↑m  ( 𝑀  ×  𝑃 ) )  ↔  ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) ) : ( 𝑀  ×  𝑃 ) ⟶ 𝐵 ) ) | 
						
							| 38 | 34 36 37 | sylancr | ⊢ ( 𝜑  →  ( ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) )  ∈  ( 𝐵  ↑m  ( 𝑀  ×  𝑃 ) )  ↔  ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) ) : ( 𝑀  ×  𝑃 ) ⟶ 𝐵 ) ) | 
						
							| 39 | 33 38 | bitr4id | ⊢ ( 𝜑  →  ( ∀ 𝑖  ∈  𝑀 ∀ 𝑘  ∈  𝑃 ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) )  ∈  𝐵  ↔  ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) )  ∈  ( 𝐵  ↑m  ( 𝑀  ×  𝑃 ) ) ) ) | 
						
							| 40 | 31 39 | mpbid | ⊢ ( 𝜑  →  ( 𝑖  ∈  𝑀 ,  𝑘  ∈  𝑃  ↦  ( 𝑅  Σg  ( 𝑗  ∈  𝑁  ↦  ( ( 𝑖 𝑋 𝑗 ) ( .r ‘ 𝑅 ) ( 𝑗 𝑌 𝑘 ) ) ) ) )  ∈  ( 𝐵  ↑m  ( 𝑀  ×  𝑃 ) ) ) | 
						
							| 41 | 10 40 | eqeltrd | ⊢ ( 𝜑  →  ( 𝑋 𝐹 𝑌 )  ∈  ( 𝐵  ↑m  ( 𝑀  ×  𝑃 ) ) ) |