| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cayhamlem1.a | ⊢ 𝐴  =  ( 𝑁  Mat  𝑅 ) | 
						
							| 2 |  | cayhamlem1.b | ⊢ 𝐵  =  ( Base ‘ 𝐴 ) | 
						
							| 3 |  | cayhamlem1.p | ⊢ 𝑃  =  ( Poly1 ‘ 𝑅 ) | 
						
							| 4 |  | cayhamlem1.y | ⊢ 𝑌  =  ( 𝑁  Mat  𝑃 ) | 
						
							| 5 |  | cayhamlem1.r | ⊢  ×   =  ( .r ‘ 𝑌 ) | 
						
							| 6 |  | cayhamlem1.s | ⊢  −   =  ( -g ‘ 𝑌 ) | 
						
							| 7 |  | cayhamlem1.0 | ⊢  0   =  ( 0g ‘ 𝑌 ) | 
						
							| 8 |  | cayhamlem1.t | ⊢ 𝑇  =  ( 𝑁  matToPolyMat  𝑅 ) | 
						
							| 9 |  | cayhamlem1.g | ⊢ 𝐺  =  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  (  0   −  ( ( 𝑇 ‘ 𝑀 )  ×  ( 𝑇 ‘ ( 𝑏 ‘ 0 ) ) ) ) ,  if ( 𝑛  =  ( 𝑠  +  1 ) ,  ( 𝑇 ‘ ( 𝑏 ‘ 𝑠 ) ) ,  if ( ( 𝑠  +  1 )  <  𝑛 ,   0  ,  ( ( 𝑇 ‘ ( 𝑏 ‘ ( 𝑛  −  1 ) ) )  −  ( ( 𝑇 ‘ 𝑀 )  ×  ( 𝑇 ‘ ( 𝑏 ‘ 𝑛 ) ) ) ) ) ) ) ) | 
						
							| 10 |  | cayhamlem1.e | ⊢  ↑   =  ( .g ‘ ( mulGrp ‘ 𝑌 ) ) | 
						
							| 11 |  | crngring | ⊢ ( 𝑅  ∈  CRing  →  𝑅  ∈  Ring ) | 
						
							| 12 | 3 4 | pmatring | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  𝑌  ∈  Ring ) | 
						
							| 13 | 11 12 | sylan2 | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing )  →  𝑌  ∈  Ring ) | 
						
							| 14 | 13 | 3adant3 | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  →  𝑌  ∈  Ring ) | 
						
							| 15 | 14 | 3ad2ant1 | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  𝑌  ∈  Ring ) | 
						
							| 16 |  | eqid | ⊢ ( mulGrp ‘ 𝑌 )  =  ( mulGrp ‘ 𝑌 ) | 
						
							| 17 |  | eqid | ⊢ ( Base ‘ 𝑌 )  =  ( Base ‘ 𝑌 ) | 
						
							| 18 | 16 17 | mgpbas | ⊢ ( Base ‘ 𝑌 )  =  ( Base ‘ ( mulGrp ‘ 𝑌 ) ) | 
						
							| 19 | 16 | ringmgp | ⊢ ( 𝑌  ∈  Ring  →  ( mulGrp ‘ 𝑌 )  ∈  Mnd ) | 
						
							| 20 | 14 19 | syl | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  →  ( mulGrp ‘ 𝑌 )  ∈  Mnd ) | 
						
							| 21 | 20 | 3ad2ant1 | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  ( mulGrp ‘ 𝑌 )  ∈  Mnd ) | 
						
							| 22 |  | simp3 | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  𝐾  ∈  ℕ0 ) | 
						
							| 23 | 8 1 2 3 4 | mat2pmatbas | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring  ∧  𝑀  ∈  𝐵 )  →  ( 𝑇 ‘ 𝑀 )  ∈  ( Base ‘ 𝑌 ) ) | 
						
							| 24 | 11 23 | syl3an2 | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  →  ( 𝑇 ‘ 𝑀 )  ∈  ( Base ‘ 𝑌 ) ) | 
						
							| 25 | 24 | 3ad2ant1 | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  ( 𝑇 ‘ 𝑀 )  ∈  ( Base ‘ 𝑌 ) ) | 
						
							| 26 | 18 10 21 22 25 | mulgnn0cld | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  ( 𝐾  ↑  ( 𝑇 ‘ 𝑀 ) )  ∈  ( Base ‘ 𝑌 ) ) | 
						
							| 27 | 1 2 3 4 5 6 7 8 9 | chfacfisf | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) ) )  →  𝐺 : ℕ0 ⟶ ( Base ‘ 𝑌 ) ) | 
						
							| 28 | 11 27 | syl3anl2 | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) ) )  →  𝐺 : ℕ0 ⟶ ( Base ‘ 𝑌 ) ) | 
						
							| 29 | 28 | 3adant3 | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  𝐺 : ℕ0 ⟶ ( Base ‘ 𝑌 ) ) | 
						
							| 30 | 29 22 | ffvelcdmd | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  ( 𝐺 ‘ 𝐾 )  ∈  ( Base ‘ 𝑌 ) ) | 
						
							| 31 | 17 5 | ringcl | ⊢ ( ( 𝑌  ∈  Ring  ∧  ( 𝐾  ↑  ( 𝑇 ‘ 𝑀 ) )  ∈  ( Base ‘ 𝑌 )  ∧  ( 𝐺 ‘ 𝐾 )  ∈  ( Base ‘ 𝑌 ) )  →  ( ( 𝐾  ↑  ( 𝑇 ‘ 𝑀 ) )  ×  ( 𝐺 ‘ 𝐾 ) )  ∈  ( Base ‘ 𝑌 ) ) | 
						
							| 32 | 15 26 30 31 | syl3anc | ⊢ ( ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing  ∧  𝑀  ∈  𝐵 )  ∧  ( 𝑠  ∈  ℕ  ∧  𝑏  ∈  ( 𝐵  ↑m  ( 0 ... 𝑠 ) ) )  ∧  𝐾  ∈  ℕ0 )  →  ( ( 𝐾  ↑  ( 𝑇 ‘ 𝑀 ) )  ×  ( 𝐺 ‘ 𝐾 ) )  ∈  ( Base ‘ 𝑌 ) ) |