| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sprsymrelf.p |  | 
						
							| 2 |  | sprsymrelf.r |  | 
						
							| 3 |  | sprsymrelf.f |  | 
						
							| 4 | 1 2 3 | sprsymrelf |  | 
						
							| 5 | 1 2 3 | sprsymrelfv |  | 
						
							| 6 | 1 2 3 | sprsymrelfv |  | 
						
							| 7 | 5 6 | eqeqan12d |  | 
						
							| 8 | 1 | eleq2i |  | 
						
							| 9 |  | vex |  | 
						
							| 10 | 9 | elpw |  | 
						
							| 11 | 8 10 | bitri |  | 
						
							| 12 | 1 | eleq2i |  | 
						
							| 13 |  | vex |  | 
						
							| 14 | 13 | elpw |  | 
						
							| 15 | 12 14 | bitri |  | 
						
							| 16 |  | sprsymrelf1lem |  | 
						
							| 17 | 16 | imp |  | 
						
							| 18 |  | eqcom |  | 
						
							| 19 |  | sprsymrelf1lem |  | 
						
							| 20 | 18 19 | biimtrid |  | 
						
							| 21 | 20 | ancoms |  | 
						
							| 22 | 21 | imp |  | 
						
							| 23 | 17 22 | eqssd |  | 
						
							| 24 | 23 | ex |  | 
						
							| 25 | 11 15 24 | syl2anb |  | 
						
							| 26 | 7 25 | sylbid |  | 
						
							| 27 | 26 | rgen2 |  | 
						
							| 28 |  | dff13 |  | 
						
							| 29 | 4 27 28 | mpbir2an |  |