| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ssel |  | 
						
							| 2 | 1 | alrimiv |  | 
						
							| 3 | 2 | alrimivv |  | 
						
							| 4 |  | elvvv |  | 
						
							| 5 |  | eleq1 |  | 
						
							| 6 |  | eleq1 |  | 
						
							| 7 | 5 6 | imbi12d |  | 
						
							| 8 | 7 | biimprcd |  | 
						
							| 9 | 8 | alimi |  | 
						
							| 10 |  | 19.23v |  | 
						
							| 11 | 9 10 | sylib |  | 
						
							| 12 | 11 | 2alimi |  | 
						
							| 13 |  | 19.23vv |  | 
						
							| 14 | 12 13 | sylib |  | 
						
							| 15 | 4 14 | biimtrid |  | 
						
							| 16 | 15 | com23 |  | 
						
							| 17 | 16 | a2d |  | 
						
							| 18 | 17 | alimdv |  | 
						
							| 19 |  | df-ss |  | 
						
							| 20 |  | df-ss |  | 
						
							| 21 | 18 19 20 | 3imtr4g |  | 
						
							| 22 | 21 | com12 |  | 
						
							| 23 | 3 22 | impbid2 |  |