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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 0 |
| 4 | 10 |
| 5 | -48 |
| 6 | 168 |
| 7 | 3456 |
| 8 | -29376 |
| 9 | -178560 |
| 10 | 0 |
| 11 | 2995200 |
| 12 | 0 |
| 13 | -45158400 |
| 14 | 1045094400 |
| 15 | -14636482560 |
| 16 | -122918584320 |
| 17 | -370845941760 |
| 18 | 12983695441920 |
| 19 | -1545691830681600 |
| 20 | -62521904633610240 |
| 21 | 785989658251100160 |
| 22 | -2445553599452282880 |
[2,3,0,10,-48,168,3456,-29376,-178560,0,2995200,0, -45158400,1045094400,-14636482560,-122918584320, -370845941760,12983695441920,-1545691830681600, -62521904633610240,785989658251100160, -2445553599452282880] |