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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | -6 |
| 3 | 57 |
| 4 | -294 |
| 5 | 1884 |
| 6 | -13011 |
| 7 | 95178 |
| 8 | -712293 |
| 9 | 5448495 |
| 10 | -42444375 |
| 11 | 335392941 |
| 12 | -2681006280 |
| 13 | 21639853488 |
| 14 | -176113016241 |
| 15 | 1443450932445 |
| 16 | -11903668996713 |
| 17 | 98695838478585 |
| 18 | -822212761531101 |
| 19 | 6878755556938029 |
| 20 | -57767592614370576 |
| 21 | 486792969548157129 |
[1,3,-6,57,-294,1884,-13011,95178,-712293,5448495, -42444375,335392941,-2681006280,21639853488, -176113016241,1443450932445,-11903668996713, 98695838478585,-822212761531101,6878755556938029, -57767592614370576,486792969548157129] |