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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 18 |
| 4 | 38 |
| 5 | 88 |
| 6 | 188 |
| 7 | 388 |
| 8 | 888 |
| 9 | 1888 |
| 10 | 3888 |
| 11 | 8888 |
| 12 | 18888 |
| 13 | 38888 |
| 14 | 88888 |
| 15 | 188888 |
| 16 | 388888 |
| 17 | 888888 |
| 18 | 1888888 |
| 19 | 3888888 |
| 20 | 8888888 |
| 21 | 18888888 |
| 22 | 38888888 |
| 23 | 88888888 |
| 24 | 188888888 |
| 25 | 388888888 |
| 26 | 888888888 |
| 27 | 1888888888 |
| 28 | 3888888888 |
| 29 | 8888888888 |
[1,3,8,18,38,88,188,388,888,1888,3888,8888,18888, 38888,88888,188888,388888,888888,1888888,3888888, 8888888,18888888,38888888,88888888,188888888, 388888888,888888888,1888888888,3888888888, 8888888888] |