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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 18 |
| 2 | 188 |
| 3 | 1888 |
| 4 | 18888 |
| 5 | 188888 |
| 6 | 1888888 |
| 7 | 18888888 |
| 8 | 188888888 |
| 9 | 1888888888 |
| 10 | 18888888888 |
| 11 | 188888888888 |
| 12 | 1888888888888 |
| 13 | 18888888888888 |
| 14 | 188888888888888 |
| 15 | 1888888888888888 |
| 16 | 18888888888888888 |
| 17 | 188888888888888888 |
| 18 | 1888888888888888888 |
| 19 | 18888888888888888888 |
[1,18,188,1888,18888,188888,1888888,18888888, 188888888,1888888888,18888888888,188888888888, 1888888888888,18888888888888,188888888888888, 1888888888888888,18888888888888888, 188888888888888888,1888888888888888888, 18888888888888888888] |