Step |
Hyp |
Ref |
Expression |
1 |
|
sitmval.d |
|
2 |
|
sitmval.1 |
|
3 |
|
sitmval.2 |
|
4 |
|
elex |
|
5 |
2 4
|
syl |
|
6 |
|
oveq1 |
|
7 |
6
|
dmeqd |
|
8 |
|
fveq2 |
|
9 |
|
ofeq |
|
10 |
8 9
|
syl |
|
11 |
10
|
oveqd |
|
12 |
11
|
fveq2d |
|
13 |
7 7 12
|
mpoeq123dv |
|
14 |
|
oveq2 |
|
15 |
14
|
dmeqd |
|
16 |
|
oveq2 |
|
17 |
1
|
eqcomi |
|
18 |
|
ofeq |
|
19 |
17 18
|
mp1i |
|
20 |
19
|
oveqd |
|
21 |
16 20
|
fveq12d |
|
22 |
15 15 21
|
mpoeq123dv |
|
23 |
|
df-sitm |
|
24 |
|
ovex |
|
25 |
24
|
dmex |
|
26 |
25 25
|
mpoex |
|
27 |
13 22 23 26
|
ovmpo |
|
28 |
5 3 27
|
syl2anc |
|