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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 28 |
| 5 | 88 |
| 6 | 288 |
| 7 | 888 |
| 8 | 2888 |
| 9 | 8888 |
| 10 | 28888 |
| 11 | 88888 |
| 12 | 288888 |
| 13 | 888888 |
| 14 | 2888888 |
| 15 | 8888888 |
| 16 | 28888888 |
| 17 | 88888888 |
| 18 | 288888888 |
| 19 | 888888888 |
| 20 | 2888888888 |
| 21 | 8888888888 |
| 22 | 28888888888 |
| 23 | 88888888888 |
| 24 | 288888888888 |
| 25 | 888888888888 |
| 26 | 2888888888888 |
| 27 | 8888888888888 |
| 28 | 28888888888888 |
[1,2,8,28,88,288,888,2888,8888,28888,88888,288888, 888888,2888888,8888888,28888888,88888888, 288888888,888888888,2888888888,8888888888, 28888888888,88888888888,288888888888,888888888888, 2888888888888,8888888888888,28888888888888] |