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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 4999 |
| 3 | 267004 |
| 4 | 5207128 |
| 5 | 55191061 |
| 6 | 389769865 |
| 7 | 2062131616 |
| 8 | 8794967112 |
| 9 | 31750272891 |
| 10 | 100377252987 |
| 11 | 284840809660 |
| 12 | 738995422048 |
| 13 | 1777772706385 |
| 14 | 4009552754989 |
| 15 | 8552986503328 |
| 16 | 17379265831600 |
| 17 | 33835476742695 |
[15,4999,267004,5207128,55191061,389769865, 2062131616,8794967112,31750272891,100377252987, 284840809660,738995422048,1777772706385, 4009552754989,8552986503328,17379265831600, 33835476742695] |