Description: Lemma 1 for 2pthd . (Contributed by AV, 14-Feb-2021)
Ref | Expression | ||
---|---|---|---|
Hypotheses | 2wlkd.p | |
|
2wlkd.f | |
||
2wlkd.s | |
||
2wlkd.n | |
||
Assertion | 2pthdlem1 | |
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 | |