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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 9 |
| 2 | 99 |
| 3 | 333 |
| 4 | 7497 |
| 5 | 99999 |
| 6 | 333333 |
| 7 | 2842857 |
| 8 | 49999986 |
| 9 | 111111111 |
| 10 | 9999999999 |
| 11 | 99909090909 |
| 12 | 249999999999 |
| 13 | 2299923076923 |
| 14 | 21427857142857 |
| 15 | 333333333333333 |
| 16 | 2499999999999993 |
| 17 | 11764705294117647 |
| 18 | 111111111111111111 |
| 19 | 1526315788947368421 |
[0,9,99,333,7497,99999,333333,2842857,49999986, 111111111,9999999999,99909090909,249999999999, 2299923076923,21427857142857,333333333333333, 2499999999999993,11764705294117647, 111111111111111111,1526315788947368421] |