Step |
Hyp |
Ref |
Expression |
1 |
|
3wlkd.p |
|
2 |
|
3wlkd.f |
|
3 |
|
3wlkd.s |
|
4 |
|
3wlkd.n |
|
5 |
|
3wlkd.e |
|
6 |
|
3wlkd.v |
|
7 |
|
3wlkd.i |
|
8 |
|
3trld.n |
|
9 |
|
s4cli |
|
10 |
1 9
|
eqeltri |
|
11 |
10
|
a1i |
|
12 |
2
|
fveq2i |
|
13 |
|
s3len |
|
14 |
12 13
|
eqtri |
|
15 |
|
4m1e3 |
|
16 |
1
|
fveq2i |
|
17 |
|
s4len |
|
18 |
16 17
|
eqtr2i |
|
19 |
18
|
oveq1i |
|
20 |
14 15 19
|
3eqtr2i |
|
21 |
1 2 3 4
|
3pthdlem1 |
|
22 |
|
eqid |
|
23 |
1 2 3 4 5 6 7 8
|
3trld |
|
24 |
11 20 21 22 23
|
pthd |
|