Step |
Hyp |
Ref |
Expression |
1 |
|
elfz2nn0 |
|
2 |
|
simpl1 |
|
3 |
|
necom |
|
4 |
|
nn0re |
|
5 |
|
nn0re |
|
6 |
|
ltlen |
|
7 |
4 5 6
|
syl2an |
|
8 |
7
|
bicomd |
|
9 |
|
elnn0z |
|
10 |
|
0red |
|
11 |
|
zre |
|
12 |
11
|
adantr |
|
13 |
5
|
adantl |
|
14 |
|
lelttr |
|
15 |
10 12 13 14
|
syl3anc |
|
16 |
|
nn0z |
|
17 |
|
elnnz |
|
18 |
17
|
simplbi2 |
|
19 |
16 18
|
syl |
|
20 |
19
|
adantl |
|
21 |
15 20
|
syld |
|
22 |
21
|
expd |
|
23 |
22
|
impancom |
|
24 |
9 23
|
sylbi |
|
25 |
24
|
imp |
|
26 |
8 25
|
sylbid |
|
27 |
26
|
expd |
|
28 |
3 27
|
syl7bi |
|
29 |
28
|
3impia |
|
30 |
29
|
imp |
|
31 |
8
|
biimpd |
|
32 |
31
|
exp4b |
|
33 |
32
|
3imp |
|
34 |
3 33
|
syl5bi |
|
35 |
34
|
imp |
|
36 |
2 30 35
|
3jca |
|
37 |
36
|
ex |
|
38 |
1 37
|
sylbi |
|
39 |
38
|
impcom |
|
40 |
|
elfzo0 |
|
41 |
39 40
|
sylibr |
|