Step |
Hyp |
Ref |
Expression |
1 |
|
nbgrel.v |
|
2 |
|
nbgrel.e |
|
3 |
1
|
nbgrcl |
|
4 |
3
|
pm4.71ri |
|
5 |
1 2
|
nbgrval |
|
6 |
5
|
eleq2d |
|
7 |
|
preq2 |
|
8 |
7
|
sseq1d |
|
9 |
8
|
rexbidv |
|
10 |
9
|
elrab |
|
11 |
|
eldifsn |
|
12 |
11
|
anbi1i |
|
13 |
10 12
|
bitri |
|
14 |
6 13
|
syl6bb |
|
15 |
14
|
pm5.32i |
|
16 |
|
df-3an |
|
17 |
|
anass |
|
18 |
|
ancom |
|
19 |
18
|
anbi1i |
|
20 |
17 19
|
bitr3i |
|
21 |
20
|
anbi1i |
|
22 |
|
anass |
|
23 |
16 21 22
|
3bitr2ri |
|
24 |
15 23
|
bitri |
|
25 |
4 24
|
bitri |
|