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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 19 |
| 3 | 199 |
| 4 | 1999 |
| 5 | 19997 |
| 6 | 199999 |
| 7 | 2999999 |
| 8 | 19999999 |
| 9 | 199999991 |
| 10 | 1999999973 |
| 11 | 19999999967 |
| 12 | 299999999989 |
| 13 | 1999999999981 |
| 14 | 19999999999997 |
| 15 | 399999999999997 |
| 16 | 1999999999999943 |
| 17 | 49999999999999993 |
| 18 | 199999999999999949 |
| 19 | 1999999999999999909 |
| 20 | 19999999999999999939 |
[2,19,199,1999,19997,199999,2999999,19999999, 199999991,1999999973,19999999967,299999999989, 1999999999981,19999999999997,399999999999997, 1999999999999943,49999999999999993, 199999999999999949,1999999999999999909, 19999999999999999939] |