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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 61 |
| 5 | 822 |
| 6 | 18154 |
| 7 | 617675 |
| 8 | 30888596 |
| 9 | 2192816760 |
| 10 | 215488096587 |
| 11 | 28791414081916 |
| 12 | 5165908492061926 |
| 13 | 1234777416771739141 |
| 14 | 391374602835914994534 |
| 15 | 164188178238479142509452 |
[1,2,8,61,822,18154,617675,30888596,2192816760, 215488096587,28791414081916,5165908492061926, 1234777416771739141,391374602835914994534, 164188178238479142509452] |