| Step |
Hyp |
Ref |
Expression |
| 1 |
|
seqseq123d.1 |
|
| 2 |
|
seqseq123d.2 |
|
| 3 |
|
seqseq123d.3 |
|
| 4 |
2
|
oveqd |
|
| 5 |
3
|
fveq1d |
|
| 6 |
5
|
oveq2d |
|
| 7 |
4 6
|
eqtrd |
|
| 8 |
7
|
opeq2d |
|
| 9 |
8
|
mpoeq3dv |
|
| 10 |
3 1
|
fveq12d |
|
| 11 |
1 10
|
opeq12d |
|
| 12 |
|
rdgeq12 |
|
| 13 |
9 11 12
|
syl2anc |
|
| 14 |
13
|
imaeq1d |
|
| 15 |
|
df-seqs |
|
| 16 |
|
df-seqs |
|
| 17 |
14 15 16
|
3eqtr4g |
|