Step |
Hyp |
Ref |
Expression |
1 |
|
isubgriedg.v |
|
2 |
|
isubgriedg.e |
|
3 |
|
ssidd |
|
4 |
1 2
|
isisubgr |
|
5 |
3 4
|
mpdan |
|
6 |
2
|
uhgrfun |
|
7 |
|
funrel |
|
8 |
6 7
|
syl |
|
9 |
1 2
|
uhgrf |
|
10 |
|
ffvelcdm |
|
11 |
|
eldifi |
|
12 |
11
|
elpwid |
|
13 |
10 12
|
syl |
|
14 |
13
|
rabeqcda |
|
15 |
14
|
eqimsscd |
|
16 |
9 15
|
syl |
|
17 |
|
relssres |
|
18 |
8 16 17
|
syl2anc |
|
19 |
18
|
opeq2d |
|
20 |
5 19
|
eqtrd |
|