Step |
Hyp |
Ref |
Expression |
1 |
|
neeq1 |
|
2 |
|
eqeq2 |
|
3 |
2
|
rexbidv |
|
4 |
1 3
|
imbi12d |
|
5 |
|
neeq1 |
|
6 |
|
eqeq2 |
|
7 |
6
|
rexbidv |
|
8 |
5 7
|
imbi12d |
|
9 |
|
neeq1 |
|
10 |
|
eqeq2 |
|
11 |
10
|
rexbidv |
|
12 |
9 11
|
imbi12d |
|
13 |
|
neeq1 |
|
14 |
|
eqeq2 |
|
15 |
14
|
rexbidv |
|
16 |
13 15
|
imbi12d |
|
17 |
|
df-ne |
|
18 |
|
eqid |
|
19 |
18
|
pm2.24i |
|
20 |
17 19
|
sylbi |
|
21 |
|
id |
|
22 |
|
oveq1 |
|
23 |
22
|
eqeq1d |
|
24 |
23
|
adantl |
|
25 |
|
eqidd |
|
26 |
21 24 25
|
rspcedvd |
|
27 |
26
|
2a1d |
|
28 |
4 8 12 16 20 27
|
nnind |
|
29 |
28
|
imp |
|