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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 81 |
| 3 | 387 |
| 4 | 1849 |
| 5 | 10535 |
| 6 | 60025 |
| 7 | 327075 |
| 8 | 1782225 |
| 9 | 9840285 |
| 10 | 54331641 |
| 11 | 298827711 |
| 12 | 1643572681 |
| 13 | 9050656627 |
| 14 | 49839223009 |
| 15 | 274344889595 |
| 16 | 1510158343225 |
| 17 | 8313840821405 |
| 18 | 45770001214609 |
| 19 | 251966391900979 |
| 20 | 1387088943911449 |
[9,81,387,1849,10535,60025,327075,1782225,9840285, 54331641,298827711,1643572681,9050656627, 49839223009,274344889595,1510158343225, 8313840821405,45770001214609,251966391900979, 1387088943911449] |