| Step | Hyp | Ref | Expression | 
						
							| 1 |  | tocycval.1 |  | 
						
							| 2 |  | tocycfv.d |  | 
						
							| 3 |  | tocycfv.w |  | 
						
							| 4 |  | tocycfv.1 |  | 
						
							| 5 | 1 2 3 4 | tocycfv |  | 
						
							| 6 | 5 | reseq1d |  | 
						
							| 7 |  | fnresi |  | 
						
							| 8 | 7 | a1i |  | 
						
							| 9 |  | 1zzd |  | 
						
							| 10 |  | cshwfn |  | 
						
							| 11 | 3 9 10 | syl2anc |  | 
						
							| 12 |  | f1f1orn |  | 
						
							| 13 |  | f1ocnv |  | 
						
							| 14 |  | f1ofn |  | 
						
							| 15 | 4 12 13 14 | 4syl |  | 
						
							| 16 |  | dfdm4 |  | 
						
							| 17 |  | wrddm |  | 
						
							| 18 | 3 17 | syl |  | 
						
							| 19 |  | ssidd |  | 
						
							| 20 | 18 19 | eqsstrd |  | 
						
							| 21 | 16 20 | eqsstrrid |  | 
						
							| 22 |  | fnco |  | 
						
							| 23 | 11 15 21 22 | syl3anc |  | 
						
							| 24 |  | disjdifr |  | 
						
							| 25 | 24 | a1i |  | 
						
							| 26 |  | fnunres1 |  | 
						
							| 27 | 8 23 25 26 | syl3anc |  | 
						
							| 28 | 6 27 | eqtrd |  |