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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 15 |
| 4 | 204 |
| 5 | 4095 |
| 6 | 109668 |
| 7 | 3689595 |
| 8 | 149846840 |
| 9 | 7141879503 |
| 10 | 391139588190 |
| 11 | 24218296445200 |
| 12 | 1673538279265020 |
| 13 | 127715832778905150 |
| 14 | 10670643284149377480 |
| 15 | 968929726650218004435 |
| 16 | 95024894699780159868144 |
| 17 | 10011211830149283223044015 |
[1,2,15,204,4095,109668,3689595,149846840, 7141879503,391139588190,24218296445200, 1673538279265020,127715832778905150, 10670643284149377480,968929726650218004435, 95024894699780159868144, 10011211830149283223044015] |