| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sbcor |  | 
						
							| 2 | 1 | a1i |  | 
						
							| 3 |  | df-3or |  | 
						
							| 4 | 3 | bicomi |  | 
						
							| 5 | 4 | sbcbii |  | 
						
							| 6 | 5 | a1i |  | 
						
							| 7 |  | sbcor |  | 
						
							| 8 | 7 | a1i |  | 
						
							| 9 | 8 | orbi1d |  | 
						
							| 10 | 2 6 9 | 3bitr3d |  | 
						
							| 11 |  | df-3or |  | 
						
							| 12 | 10 11 | bitr4di |  | 
						
							| 13 | 12 | dfvd1ir |  | 
						
							| 14 |  | sbcel2gv |  | 
						
							| 15 | 14 | dfvd1ir |  | 
						
							| 16 |  | sbcel1v |  | 
						
							| 17 |  | eqsbc2 |  | 
						
							| 18 | 17 | dfvd1ir |  | 
						
							| 19 |  | 3orbi123 |  | 
						
							| 20 | 19 | 3impexpbicomi |  | 
						
							| 21 | 15 16 18 20 | e101 |  | 
						
							| 22 |  | biantr |  | 
						
							| 23 | 13 21 22 | e11an |  | 
						
							| 24 | 23 | in1 |  |