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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 99 |
| 3 | 9009 |
| 4 | 909909 |
| 5 | 9009009009 |
| 6 | 90099099099009 |
| 7 | 90009090099009090009 |
| 8 | 9000009009009009009009000009 |
| 9 | 90000090099090099099099009099009000009 |
[9,99,9009,909909,9009009009,90099099099009, 90009090099009090009,9000009009009009009009000009, 90000090099090099099099009099009000009] |