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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -4 |
| 3 | 51 |
| 4 | -996 |
| 5 | 27120 |
| 6 | -943602 |
| 7 | 40023354 |
| 8 | -2002953432 |
| 9 | 115536775248 |
| 10 | -7547711366880 |
| 11 | 550798542893808 |
| 12 | -44409102801760584 |
| 13 | 3920444594317227600 |
| 14 | -376109365694009875704 |
| 15 | 38961901445878423746360 |
| 16 | -4334496557343337848950208 |
| 17 | 515407133679990302374396416 |
[1,1,-4,51,-996,27120,-943602,40023354, -2002953432,115536775248,-7547711366880, 550798542893808,-44409102801760584, 3920444594317227600,-376109365694009875704, 38961901445878423746360, -4334496557343337848950208, 515407133679990302374396416] |