| Step | Hyp | Ref | Expression | 
						
							| 1 |  | pwfseqlem4.g |  | 
						
							| 2 |  | pwfseqlem4.x |  | 
						
							| 3 |  | pwfseqlem4.h |  | 
						
							| 4 |  | pwfseqlem4.ps |  | 
						
							| 5 |  | pwfseqlem4.k |  | 
						
							| 6 |  | pwfseqlem4.d |  | 
						
							| 7 | 1 | adantr |  | 
						
							| 8 |  | f1f |  | 
						
							| 9 | 7 8 | syl |  | 
						
							| 10 |  | ssrab2 |  | 
						
							| 11 |  | simprl1 |  | 
						
							| 12 | 4 11 | sylan2b |  | 
						
							| 13 | 10 12 | sstrid |  | 
						
							| 14 |  | vex |  | 
						
							| 15 | 14 | rabex |  | 
						
							| 16 | 15 | elpw |  | 
						
							| 17 | 13 16 | sylibr |  | 
						
							| 18 | 9 17 | ffvelcdmd |  | 
						
							| 19 | 6 18 | eqeltrid |  | 
						
							| 20 |  | pm5.19 |  | 
						
							| 21 | 5 | adantr |  | 
						
							| 22 |  | f1f |  | 
						
							| 23 | 21 22 | syl |  | 
						
							| 24 |  | ffvelcdm |  | 
						
							| 25 | 23 24 | sylancom |  | 
						
							| 26 |  | f1f1orn |  | 
						
							| 27 | 21 26 | syl |  | 
						
							| 28 |  | f1ocnvfv1 |  | 
						
							| 29 | 27 28 | sylancom |  | 
						
							| 30 |  | f1fn |  | 
						
							| 31 | 7 30 | syl |  | 
						
							| 32 |  | fnfvelrn |  | 
						
							| 33 | 31 17 32 | syl2anc |  | 
						
							| 34 | 6 33 | eqeltrid |  | 
						
							| 35 | 34 | adantr |  | 
						
							| 36 | 29 35 | eqeltrd |  | 
						
							| 37 |  | fveq2 |  | 
						
							| 38 | 37 | eleq1d |  | 
						
							| 39 |  | id |  | 
						
							| 40 |  | 2fveq3 |  | 
						
							| 41 | 39 40 | eleq12d |  | 
						
							| 42 | 41 | notbid |  | 
						
							| 43 | 38 42 | anbi12d |  | 
						
							| 44 |  | fveq2 |  | 
						
							| 45 | 44 | eleq1d |  | 
						
							| 46 |  | id |  | 
						
							| 47 |  | 2fveq3 |  | 
						
							| 48 | 46 47 | eleq12d |  | 
						
							| 49 | 48 | notbid |  | 
						
							| 50 | 45 49 | anbi12d |  | 
						
							| 51 | 50 | cbvrabv |  | 
						
							| 52 | 43 51 | elrab2 |  | 
						
							| 53 |  | anass |  | 
						
							| 54 | 52 53 | bitr4i |  | 
						
							| 55 | 54 | baib |  | 
						
							| 56 | 25 36 55 | syl2anc |  | 
						
							| 57 | 29 6 | eqtrdi |  | 
						
							| 58 | 57 | fveq2d |  | 
						
							| 59 |  | f1f1orn |  | 
						
							| 60 | 7 59 | syl |  | 
						
							| 61 |  | f1ocnvfv1 |  | 
						
							| 62 | 60 17 61 | syl2anc |  | 
						
							| 63 | 62 | adantr |  | 
						
							| 64 | 58 63 | eqtrd |  | 
						
							| 65 | 64 | eleq2d |  | 
						
							| 66 | 65 | notbid |  | 
						
							| 67 | 56 66 | bitrd |  | 
						
							| 68 | 67 | ex |  | 
						
							| 69 | 20 68 | mtoi |  | 
						
							| 70 | 19 69 | eldifd |  |