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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 15 |
| 4 | 2605 |
| 5 | 336017 |
| 6 | 12353030 |
| 7 | 212518051 |
| 8 | 2254248571 |
| 9 | 17095114982 |
[0,0,15,2605,336017,12353030,212518051,2254248571, 17095114982] |