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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 120 |
| 6 | -360 |
| 7 | 1680 |
| 8 | -10080 |
| 9 | 72576 |
| 10 | 1209600 |
| 11 | -14256000 |
| 12 | 159667200 |
| 13 | -1902700800 |
| 14 | 24458353920 |
| 15 | -120860812800 |
| 16 | -193037644800 |
| 17 | 23690780467200 |
| 18 | -646842994237440 |
| 19 | 14916006359654400 |
| 20 | -230812655044608000 |
| 21 | 3182953434006528000 |
| 22 | -37667817509059584000 |
[1,0,0,0,0,120,-360,1680,-10080,72576,1209600, -14256000,159667200,-1902700800,24458353920, -120860812800,-193037644800,23690780467200, -646842994237440,14916006359654400, -230812655044608000,3182953434006528000, -37667817509059584000] |