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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 1 |
| 8 | 28 |
| 9 | 5376 |
| 10 | 3568950 |
| 11 | 6258582792 |
| 12 | 25002294181788 |
| 13 | 205392847313891952 |
| 14 | 3209584611412062072189 |
| 15 | 89660154903506596076142475 |
| 16 | 4255300535932491203339640563104 |
| 17 | 328814773250544726322649425157897056 |
| 18 | 39898110763361703664060940279190531023640 |
[0,0,0,0,0,1,1,28,5376,3568950,6258582792, 25002294181788,205392847313891952, 3209584611412062072189,89660154903506596076142475, 4255300535932491203339640563104, 328814773250544726322649425157897056, 39898110763361703664060940279190531023640] |