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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 0 |
| 3 | 999 |
| 4 | 9009 |
| 5 | 99999 |
| 6 | 906609 |
| 7 | 9999999 |
| 8 | 99000099 |
| 9 | 999969999 |
| 10 | 9966006699 |
| 11 | 99999999999 |
| 12 | 999000000999 |
| 13 | 9999998999999 |
| 14 | 99956644665999 |
| 15 | 999999999999999 |
| 16 | 9999000000009999 |
| 17 | 99999999799999999 |
| 18 | 999900665566009999 |
| 19 | 9999999997999999999 |
| 20 | 99999834000043899999 |
| 21 | 999999999999999999999 |
| 22 | 9999994020000204999999 |
| 23 | 99999999999899999999999 |
[9,0,999,9009,99999,906609,9999999,99000099, 999969999,9966006699,99999999999,999000000999, 9999998999999,99956644665999,999999999999999, 9999000000009999,99999999799999999, 999900665566009999,9999999997999999999, 99999834000043899999,999999999999999999999, 9999994020000204999999,99999999999899999999999] |