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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 19 |
| 4 | 99 |
| 5 | 119 |
| 6 | 199 |
| 7 | 999 |
| 8 | 1199 |
| 9 | 1999 |
| 10 | 9999 |
| 11 | 19999 |
| 12 | 99999 |
| 13 | 119999 |
| 14 | 199999 |
| 15 | 999999 |
| 16 | 1199999 |
| 17 | 1999999 |
| 18 | 9999999 |
| 19 | 19999999 |
| 20 | 99999999 |
| 21 | 119999999 |
| 22 | 199999999 |
| 23 | 999999999 |
| 24 | 1199999999 |
| 25 | 1999999999 |
| 26 | 9999999999 |
| 27 | 19999999999 |
| 28 | 99999999999 |
| 29 | 119999999999 |
| 30 | 199999999999 |
| 31 | 999999999999 |
[1,9,19,99,119,199,999,1199,1999,9999,19999,99999, 119999,199999,999999,1199999,1999999,9999999, 19999999,99999999,119999999,199999999,999999999, 1199999999,1999999999,9999999999,19999999999, 99999999999,119999999999,199999999999, 999999999999] |