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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 17 |
| 3 | 81 |
| 4 | 547 |
| 5 | 2571 |
| 6 | 13397 |
| 7 | 78101 |
| 8 | 423957 |
| 9 | 2255611 |
| 10 | 12173719 |
| 11 | 66864485 |
| 12 | 361733507 |
| 13 | 1953439221 |
| 14 | 10607016995 |
| 15 | 57610139877 |
| 16 | 312099473393 |
| 17 | 1691511381425 |
| 18 | 9176876436943 |
| 19 | 49767044309153 |
| 20 | 269799849310117 |
| 21 | 1462993236129599 |
[1,17,81,547,2571,13397,78101,423957,2255611, 12173719,66864485,361733507,1953439221, 10607016995,57610139877,312099473393, 1691511381425,9176876436943,49767044309153, 269799849310117,1462993236129599] |