| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rexpen |  | 
						
							| 2 |  | eleq1w |  | 
						
							| 3 |  | eleq1w |  | 
						
							| 4 | 2 3 | bi2anan9 |  | 
						
							| 5 |  | oveq2 |  | 
						
							| 6 |  | oveq12 |  | 
						
							| 7 | 5 6 | sylan2 |  | 
						
							| 8 | 7 | eqeq2d |  | 
						
							| 9 | 4 8 | anbi12d |  | 
						
							| 10 | 9 | cbvoprab12v |  | 
						
							| 11 |  | df-mpo |  | 
						
							| 12 | 10 11 | eqtr4i |  | 
						
							| 13 | 12 | cnref1o |  | 
						
							| 14 |  | reex |  | 
						
							| 15 | 14 14 | xpex |  | 
						
							| 16 | 15 | f1oen |  | 
						
							| 17 | 13 16 | ax-mp |  | 
						
							| 18 | 1 17 | entr3i |  | 
						
							| 19 |  | rpnnen |  | 
						
							| 20 | 18 19 | entr3i |  |