| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ndmaov.1 |  | 
						
							| 2 |  | ndmaov.6 |  | 
						
							| 3 | 2 | eleq2i |  | 
						
							| 4 |  | opelxp |  | 
						
							| 5 | 3 4 | bitri |  | 
						
							| 6 |  | aovvdm |  | 
						
							| 7 | 1 | eleq2i |  | 
						
							| 8 |  | opelxp |  | 
						
							| 9 | 7 8 | bitri |  | 
						
							| 10 |  | 3anass |  | 
						
							| 11 | 10 | simplbi2com |  | 
						
							| 12 | 9 11 | sylbi |  | 
						
							| 13 | 6 12 | syl |  | 
						
							| 14 | 13 | impcom |  | 
						
							| 15 | 5 14 | sylbi |  | 
						
							| 16 |  | ndmaov |  | 
						
							| 17 | 15 16 | nsyl5 |  | 
						
							| 18 | 1 | eleq2i |  | 
						
							| 19 |  | opelxp |  | 
						
							| 20 | 18 19 | bitri |  | 
						
							| 21 |  | aovvdm |  | 
						
							| 22 | 2 | eleq2i |  | 
						
							| 23 |  | opelxp |  | 
						
							| 24 | 22 23 | bitri |  | 
						
							| 25 | 2 | eleq2i |  | 
						
							| 26 |  | opelxp |  | 
						
							| 27 | 25 26 | bitri |  | 
						
							| 28 |  | simpll |  | 
						
							| 29 |  | simprr |  | 
						
							| 30 |  | simplr |  | 
						
							| 31 | 28 29 30 | 3jca |  | 
						
							| 32 | 31 | ex |  | 
						
							| 33 | 27 32 | sylbi |  | 
						
							| 34 |  | aovvdm |  | 
						
							| 35 | 33 34 | syl11 |  | 
						
							| 36 | 24 35 | sylbi |  | 
						
							| 37 | 21 36 | syl |  | 
						
							| 38 | 37 | imp |  | 
						
							| 39 | 20 38 | sylbi |  | 
						
							| 40 |  | ndmaov |  | 
						
							| 41 | 39 40 | nsyl5 |  | 
						
							| 42 | 17 41 | eqtr4d |  |