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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | -3 |
| 4 | 5 |
| 5 | 10 |
| 6 | -116 |
| 7 | 126 |
| 8 | 6054 |
| 9 | -68760 |
| 10 | 255336 |
| 11 | 3099360 |
| 12 | -53045136 |
| 13 | 55156608 |
| 14 | 10024873104 |
| 15 | -175247246160 |
| 16 | 693221858736 |
| 17 | 29064929199744 |
| 18 | -605379922107648 |
| 19 | -445102785680256 |
| 20 | 264990555297131904 |
| 21 | -5736069117714297600 |
[0,0,1,-3,5,10,-116,126,6054,-68760,255336, 3099360,-53045136,55156608,10024873104, -175247246160,693221858736,29064929199744, -605379922107648,-445102785680256, 264990555297131904,-5736069117714297600] |