Step |
Hyp |
Ref |
Expression |
1 |
|
vex |
|
2 |
1
|
elpred |
|
3 |
|
eluzelz |
|
4 |
|
eluzelz |
|
5 |
|
zltlem1 |
|
6 |
3 4 5
|
syl2anr |
|
7 |
6
|
pm5.32da |
|
8 |
|
eluzel2 |
|
9 |
|
eluz1 |
|
10 |
8 9
|
syl |
|
11 |
10
|
anbi1d |
|
12 |
7 11
|
bitrd |
|
13 |
2 12
|
bitrd |
|
14 |
|
peano2zm |
|
15 |
4 14
|
syl |
|
16 |
8 15
|
jca |
|
17 |
16
|
biantrurd |
|
18 |
13 17
|
bitrd |
|
19 |
|
elfz2 |
|
20 |
|
df-3an |
|
21 |
20
|
anbi1i |
|
22 |
|
anass |
|
23 |
|
anass |
|
24 |
23
|
anbi2i |
|
25 |
22 24
|
bitr4i |
|
26 |
19 21 25
|
3bitri |
|
27 |
18 26
|
bitr4di |
|
28 |
27
|
eqrdv |
|