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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1680 |
| 2 | 0 |
| 3 | 0 |
| 4 | 320743643010 |
| 5 | 10058239033920 |
| 6 | 0 |
| 7 | 0 |
| 8 | 16657062087640520 |
| 9 | 62993444371397120 |
| 10 | 0 |
| 11 | 0 |
[1,1680,0,0,320743643010,10058239033920,0,0, 16657062087640520,62993444371397120,0,0] |