| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mp2pm2mp.a | ⊢ 𝐴  =  ( 𝑁  Mat  𝑅 ) | 
						
							| 2 |  | mp2pm2mp.q | ⊢ 𝑄  =  ( Poly1 ‘ 𝐴 ) | 
						
							| 3 |  | mp2pm2mp.l | ⊢ 𝐿  =  ( Base ‘ 𝑄 ) | 
						
							| 4 |  | mp2pm2mp.m | ⊢  ·   =  (  ·𝑠  ‘ 𝑃 ) | 
						
							| 5 |  | mp2pm2mp.e | ⊢ 𝐸  =  ( .g ‘ ( mulGrp ‘ 𝑃 ) ) | 
						
							| 6 |  | mp2pm2mp.y | ⊢ 𝑌  =  ( var1 ‘ 𝑅 ) | 
						
							| 7 |  | mp2pm2mp.i | ⊢ 𝐼  =  ( 𝑝  ∈  𝐿  ↦  ( 𝑖  ∈  𝑁 ,  𝑗  ∈  𝑁  ↦  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑝 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) ) ) | 
						
							| 8 |  | fveq2 | ⊢ ( 𝑝  =  𝑂  →  ( coe1 ‘ 𝑝 )  =  ( coe1 ‘ 𝑂 ) ) | 
						
							| 9 | 8 | fveq1d | ⊢ ( 𝑝  =  𝑂  →  ( ( coe1 ‘ 𝑝 ) ‘ 𝑘 )  =  ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) ) | 
						
							| 10 | 9 | oveqd | ⊢ ( 𝑝  =  𝑂  →  ( 𝑖 ( ( coe1 ‘ 𝑝 ) ‘ 𝑘 ) 𝑗 )  =  ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 ) ) | 
						
							| 11 | 10 | oveq1d | ⊢ ( 𝑝  =  𝑂  →  ( ( 𝑖 ( ( coe1 ‘ 𝑝 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) )  =  ( ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) | 
						
							| 12 | 11 | mpteq2dv | ⊢ ( 𝑝  =  𝑂  →  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑝 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) )  =  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) | 
						
							| 13 | 12 | oveq2d | ⊢ ( 𝑝  =  𝑂  →  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑝 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) )  =  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) ) | 
						
							| 14 | 13 | mpoeq3dv | ⊢ ( 𝑝  =  𝑂  →  ( 𝑖  ∈  𝑁 ,  𝑗  ∈  𝑁  ↦  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑝 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) )  =  ( 𝑖  ∈  𝑁 ,  𝑗  ∈  𝑁  ↦  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) ) ) | 
						
							| 15 |  | simp3 | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring  ∧  𝑂  ∈  𝐿 )  →  𝑂  ∈  𝐿 ) | 
						
							| 16 |  | simp1 | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring  ∧  𝑂  ∈  𝐿 )  →  𝑁  ∈  Fin ) | 
						
							| 17 |  | mpoexga | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑁  ∈  Fin )  →  ( 𝑖  ∈  𝑁 ,  𝑗  ∈  𝑁  ↦  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) )  ∈  V ) | 
						
							| 18 | 16 16 17 | syl2anc | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring  ∧  𝑂  ∈  𝐿 )  →  ( 𝑖  ∈  𝑁 ,  𝑗  ∈  𝑁  ↦  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) )  ∈  V ) | 
						
							| 19 | 7 14 15 18 | fvmptd3 | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring  ∧  𝑂  ∈  𝐿 )  →  ( 𝐼 ‘ 𝑂 )  =  ( 𝑖  ∈  𝑁 ,  𝑗  ∈  𝑁  ↦  ( 𝑃  Σg  ( 𝑘  ∈  ℕ0  ↦  ( ( 𝑖 ( ( coe1 ‘ 𝑂 ) ‘ 𝑘 ) 𝑗 )  ·  ( 𝑘 𝐸 𝑌 ) ) ) ) ) ) |