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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 15 |
| 2 | 173525 |
| 3 | 175943559810422753 |
| 4 | 229866006383458830949778967121025947053151071434926 |
[1,15,173525,175943559810422753, 22986600638345883094977896712102594705315107143492\ 6] |