| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ringdilem.b |  | 
						
							| 2 |  | ringdilem.p |  | 
						
							| 3 |  | ringdilem.t |  | 
						
							| 4 |  | eqid |  | 
						
							| 5 | 1 4 2 3 | isring |  | 
						
							| 6 | 5 | simp3bi |  | 
						
							| 7 | 6 | adantr |  | 
						
							| 8 |  | simpr1 |  | 
						
							| 9 |  | rsp |  | 
						
							| 10 | 7 8 9 | sylc |  | 
						
							| 11 |  | simpr2 |  | 
						
							| 12 |  | rsp |  | 
						
							| 13 | 10 11 12 | sylc |  | 
						
							| 14 |  | simpr3 |  | 
						
							| 15 |  | rsp |  | 
						
							| 16 | 13 14 15 | sylc |  | 
						
							| 17 | 16 | simpld |  | 
						
							| 18 | 17 | caovdig |  | 
						
							| 19 | 16 | simprd |  | 
						
							| 20 | 19 | caovdirg |  | 
						
							| 21 | 18 20 | jca |  |