Step |
Hyp |
Ref |
Expression |
1 |
|
clwwlkwwlksb.v |
|
2 |
|
nnnn0 |
|
3 |
|
ccatws1lenp1b |
|
4 |
2 3
|
sylan2 |
|
5 |
4
|
anbi2d |
|
6 |
|
simpl |
|
7 |
|
eleq1 |
|
8 |
|
len0nnbi |
|
9 |
8
|
biimprcd |
|
10 |
7 9
|
syl6bir |
|
11 |
10
|
com13 |
|
12 |
11
|
imp31 |
|
13 |
1
|
clwwlkwwlksb |
|
14 |
6 12 13
|
syl2an2r |
|
15 |
14
|
bicomd |
|
16 |
15
|
ex |
|
17 |
16
|
pm5.32rd |
|
18 |
5 17
|
bitrd |
|
19 |
2
|
adantl |
|
20 |
|
iswwlksn |
|
21 |
19 20
|
syl |
|
22 |
|
isclwwlkn |
|
23 |
22
|
a1i |
|
24 |
18 21 23
|
3bitr4rd |
|