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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 21 |
| 3 | 239 |
| 4 | 1252 |
| 5 | 9528 |
| 6 | 59839 |
| 7 | 413786 |
| 8 | 2724191 |
| 9 | 18387032 |
| 10 | 122539084 |
| 11 | 821945828 |
| 12 | 5495164996 |
| 13 | 36800032261 |
| 14 | 246231184011 |
| 15 | 1648269251345 |
| 16 | 11031030456148 |
| 17 | 73833534042745 |
| 18 | 494158034052549 |
| 19 | 3307432804186754 |
| 20 | 22136531409536410 |
[8,21,239,1252,9528,59839,413786,2724191,18387032, 122539084,821945828,5495164996,36800032261, 246231184011,1648269251345,11031030456148, 73833534042745,494158034052549,3307432804186754, 22136531409536410] |