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| n | a(n) |
|---|---|
| 1 | 109 |
| 2 | 1009 |
| 3 | 10009 |
| 4 | 1000099 |
| 5 | 1000009999 |
| 6 | 1000000999999 |
| 7 | 10000000999 |
| 8 | 1000000009 |
| 9 | 1000000000999999999 |
| 10 | 10000000000099 |
| 11 | 100000000000099 |
| 12 | 100000000000009999 |
| 13 | 10000000000000099 |
| 14 | 100000000000000099 |
| 15 | 1000000000000000009 |
[109,1009,10009,1000099,1000009999,1000000999999, 10000000999,1000000009,1000000000999999999, 10000000000099,100000000000099,100000000000009999, 10000000000000099,100000000000000099, 1000000000000000009] |