Step |
Hyp |
Ref |
Expression |
1 |
|
upwordsing.1 |
|
2 |
|
s1cl |
|
3 |
|
elab6g |
|
4 |
1 2 3
|
mp2b |
|
5 |
|
eleq1a |
|
6 |
1 2 5
|
mp2b |
|
7 |
|
fveq2 |
|
8 |
7
|
oveq1d |
|
9 |
|
s1len |
|
10 |
9
|
oveq1i |
|
11 |
|
1m1e0 |
|
12 |
10 11
|
eqtri |
|
13 |
8 12
|
eqtrdi |
|
14 |
13
|
oveq2d |
|
15 |
|
fzo0 |
|
16 |
14 15
|
eqtrdi |
|
17 |
|
rzal |
|
18 |
16 17
|
syl |
|
19 |
6 18
|
jca |
|
20 |
4 19
|
mpgbir |
|
21 |
|
df-upword |
|
22 |
20 21
|
eleqtrri |
|