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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | -3 |
| 4 | 0 |
| 5 | 30 |
| 6 | 90 |
| 7 | -588 |
| 8 | -5040 |
| 9 | 11400 |
| 10 | 325080 |
| 11 | 336072 |
| 12 | -25237080 |
| 13 | -126955920 |
| 14 | 2273150880 |
| 15 | 25210740552 |
| 16 | -217110741120 |
| 17 | -4985924326080 |
| 18 | 16380284725440 |
| 19 | 1066531842442752 |
| 20 | 1493617498611840 |
| 21 | -249776526926340480 |
| 22 | -1647997041357152640 |
| 23 | 63281386481329443072 |
[1,0,0,-3,0,30,90,-588,-5040,11400,325080,336072, -25237080,-126955920,2273150880,25210740552, -217110741120,-4985924326080,16380284725440, 1066531842442752,1493617498611840, -249776526926340480,-1647997041357152640, 63281386481329443072] |