| Step | Hyp | Ref | Expression | 
						
							| 1 |  | frege133.x |  | 
						
							| 2 |  | frege133.y |  | 
						
							| 3 |  | frege133.m |  | 
						
							| 4 |  | frege133.r |  | 
						
							| 5 |  | fvex |  | 
						
							| 6 | 5 | cnvex |  | 
						
							| 7 |  | imaexg |  | 
						
							| 8 | 6 7 | ax-mp |  | 
						
							| 9 |  | imaundir |  | 
						
							| 10 |  | imaexg |  | 
						
							| 11 | 5 10 | ax-mp |  | 
						
							| 12 |  | imai |  | 
						
							| 13 |  | snex |  | 
						
							| 14 | 12 13 | eqeltri |  | 
						
							| 15 | 11 14 | unex |  | 
						
							| 16 | 9 15 | eqeltri |  | 
						
							| 17 | 1 2 4 8 16 | frege83 |  | 
						
							| 18 | 3 | elexi |  | 
						
							| 19 | 1 | elexi |  | 
						
							| 20 | 18 19 | elimasn |  | 
						
							| 21 |  | df-br |  | 
						
							| 22 | 18 19 | brcnv |  | 
						
							| 23 | 20 21 22 | 3bitr2i |  | 
						
							| 24 |  | elun |  | 
						
							| 25 |  | df-or |  | 
						
							| 26 | 2 | elexi |  | 
						
							| 27 | 18 26 | elimasn |  | 
						
							| 28 |  | df-br |  | 
						
							| 29 | 18 26 | brcnv |  | 
						
							| 30 | 27 28 29 | 3bitr2i |  | 
						
							| 31 | 30 | notbii |  | 
						
							| 32 | 18 26 | elimasn |  | 
						
							| 33 |  | df-br |  | 
						
							| 34 | 32 33 | bitr4i |  | 
						
							| 35 | 31 34 | imbi12i |  | 
						
							| 36 | 24 25 35 | 3bitri |  | 
						
							| 37 | 36 | imbi2i |  | 
						
							| 38 | 23 37 | imbi12i |  | 
						
							| 39 | 38 | imbi2i |  | 
						
							| 40 | 3 4 | frege132 |  | 
						
							| 41 | 39 40 | sylbi |  | 
						
							| 42 | 17 41 | ax-mp |  |