| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 2wlkd.p |  | 
						
							| 2 |  | 2wlkd.f |  | 
						
							| 3 |  | 2wlkd.s |  | 
						
							| 4 |  | 2wlkd.n |  | 
						
							| 5 | 1 2 3 | 2wlkdlem3 |  | 
						
							| 6 |  | simpl |  | 
						
							| 7 |  | simpr |  | 
						
							| 8 | 6 7 | neeq12d |  | 
						
							| 9 | 8 | bicomd |  | 
						
							| 10 | 9 | 3adant3 |  | 
						
							| 11 | 10 | biimpcd |  | 
						
							| 12 | 11 | adantr |  | 
						
							| 13 | 12 | imp |  | 
						
							| 14 | 13 | a1d |  | 
						
							| 15 |  | eqid |  | 
						
							| 16 |  | eqneqall |  | 
						
							| 17 | 15 16 | mp1i |  | 
						
							| 18 |  | simpr |  | 
						
							| 19 |  | simpl |  | 
						
							| 20 | 18 19 | neeq12d |  | 
						
							| 21 |  | necom |  | 
						
							| 22 | 20 21 | bitr2di |  | 
						
							| 23 | 22 | 3adant1 |  | 
						
							| 24 | 23 | biimpcd |  | 
						
							| 25 | 24 | adantl |  | 
						
							| 26 | 25 | imp |  | 
						
							| 27 | 26 | a1d |  | 
						
							| 28 | 14 17 27 | 3jca |  | 
						
							| 29 | 4 5 28 | syl2anc |  | 
						
							| 30 | 1 | fveq2i |  | 
						
							| 31 |  | s3len |  | 
						
							| 32 | 30 31 | eqtri |  | 
						
							| 33 | 32 | oveq2i |  | 
						
							| 34 |  | fzo0to3tp |  | 
						
							| 35 | 33 34 | eqtri |  | 
						
							| 36 | 35 | raleqi |  | 
						
							| 37 |  | c0ex |  | 
						
							| 38 |  | 1ex |  | 
						
							| 39 |  | 2ex |  | 
						
							| 40 |  | neeq1 |  | 
						
							| 41 |  | fveq2 |  | 
						
							| 42 | 41 | neeq1d |  | 
						
							| 43 | 40 42 | imbi12d |  | 
						
							| 44 |  | neeq1 |  | 
						
							| 45 |  | fveq2 |  | 
						
							| 46 | 45 | neeq1d |  | 
						
							| 47 | 44 46 | imbi12d |  | 
						
							| 48 |  | neeq1 |  | 
						
							| 49 |  | fveq2 |  | 
						
							| 50 | 49 | neeq1d |  | 
						
							| 51 | 48 50 | imbi12d |  | 
						
							| 52 | 37 38 39 43 47 51 | raltp |  | 
						
							| 53 | 36 52 | bitri |  | 
						
							| 54 | 29 53 | sylibr |  | 
						
							| 55 | 2 | fveq2i |  | 
						
							| 56 |  | s2len |  | 
						
							| 57 | 55 56 | eqtri |  | 
						
							| 58 | 57 | oveq2i |  | 
						
							| 59 |  | fzo12sn |  | 
						
							| 60 | 58 59 | eqtri |  | 
						
							| 61 | 60 | raleqi |  | 
						
							| 62 |  | neeq2 |  | 
						
							| 63 |  | fveq2 |  | 
						
							| 64 | 63 | neeq2d |  | 
						
							| 65 | 62 64 | imbi12d |  | 
						
							| 66 | 38 65 | ralsn |  | 
						
							| 67 | 61 66 | bitri |  | 
						
							| 68 | 67 | ralbii |  | 
						
							| 69 | 54 68 | sylibr |  |