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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | -2 |
| 5 | -1 |
| 6 | 7 |
| 7 | 0 |
| 8 | -44 |
| 9 | 69 |
| 10 | 276 |
| 11 | -1471 |
| 12 | 675 |
| 13 | 20407 |
| 14 | -90560 |
| 15 | -20552 |
| 16 | 2141700 |
| 17 | -10558223 |
| 18 | -675239 |
| 19 | 329376824 |
| 20 | -2106253225 |
| 21 | 2364924062 |
| 22 | 67114942438 |
| 23 | -621638176430 |
| 24 | 1926931098484 |
| 25 | 14768396756732 |
| 26 | -236623058229675 |
| 27 | 1371752460097440 |
| 28 | 1098671590491324 |
[1,1,1,0,-2,-1,7,0,-44,69,276,-1471,675,20407, -90560,-20552,2141700,-10558223,-675239,329376824, -2106253225,2364924062,67114942438,-621638176430, 1926931098484,14768396756732,-236623058229675, 1371752460097440,1098671590491324] |