| Step | Hyp | Ref | Expression | 
						
							| 1 |  | zfpow |  | 
						
							| 2 |  | 19.8a |  | 
						
							| 3 |  | sp |  | 
						
							| 4 | 2 3 | imim12i |  | 
						
							| 5 | 4 | alimi |  | 
						
							| 6 | 5 | imim1i |  | 
						
							| 7 | 6 | alimi |  | 
						
							| 8 | 1 7 | eximii |  | 
						
							| 9 |  | nfnae |  | 
						
							| 10 |  | nfnae |  | 
						
							| 11 | 9 10 | nfan |  | 
						
							| 12 |  | nfnae |  | 
						
							| 13 |  | nfnae |  | 
						
							| 14 | 12 13 | nfan |  | 
						
							| 15 |  | nfv |  | 
						
							| 16 |  | nfnae |  | 
						
							| 17 |  | nfcvd |  | 
						
							| 18 |  | nfcvf |  | 
						
							| 19 | 17 18 | nfeld |  | 
						
							| 20 | 16 19 | nfexd |  | 
						
							| 21 | 20 | adantr |  | 
						
							| 22 |  | nfcvd |  | 
						
							| 23 |  | nfcvf |  | 
						
							| 24 | 22 23 | nfeld |  | 
						
							| 25 | 13 24 | nfald |  | 
						
							| 26 | 25 | adantl |  | 
						
							| 27 | 21 26 | nfimd |  | 
						
							| 28 | 15 27 | nfald |  | 
						
							| 29 | 18 17 | nfeld |  | 
						
							| 30 | 29 | adantr |  | 
						
							| 31 | 28 30 | nfimd |  | 
						
							| 32 | 14 31 | nfald |  | 
						
							| 33 |  | nfeqf2 |  | 
						
							| 34 | 33 | naecoms |  | 
						
							| 35 | 34 | adantr |  | 
						
							| 36 | 14 35 | nfan1 |  | 
						
							| 37 |  | nfnae |  | 
						
							| 38 |  | nfeqf2 |  | 
						
							| 39 | 38 | naecoms |  | 
						
							| 40 | 37 39 | nfan1 |  | 
						
							| 41 |  | elequ1 |  | 
						
							| 42 | 41 | adantl |  | 
						
							| 43 | 40 42 | exbid |  | 
						
							| 44 | 43 | adantll |  | 
						
							| 45 | 12 34 | nfan1 |  | 
						
							| 46 |  | elequ1 |  | 
						
							| 47 | 46 | adantl |  | 
						
							| 48 | 45 47 | albid |  | 
						
							| 49 | 48 | adantlr |  | 
						
							| 50 | 44 49 | imbi12d |  | 
						
							| 51 | 50 | ex |  | 
						
							| 52 | 11 27 51 | cbvald |  | 
						
							| 53 | 52 | adantr |  | 
						
							| 54 |  | elequ2 |  | 
						
							| 55 | 54 | adantl |  | 
						
							| 56 | 53 55 | imbi12d |  | 
						
							| 57 | 36 56 | albid |  | 
						
							| 58 | 57 | ex |  | 
						
							| 59 | 11 32 58 | cbvexd |  | 
						
							| 60 | 8 59 | mpbii |  | 
						
							| 61 | 60 | ex |  |