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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -248 |
| 2 | 4124 |
| 3 | -34752 |
| 4 | 213126 |
| 5 | -1057504 |
| 6 | 4530744 |
| 7 | -17333248 |
| 8 | 60655377 |
| 9 | -197230000 |
| 10 | 603096260 |
| 11 | -1749556736 |
| 12 | 4848776870 |
| 13 | -12908659008 |
| 14 | 33161242504 |
| 15 | -82505707520 |
| 16 | 199429765972 |
| 17 | -469556091240 |
| 18 | 1079330385764 |
| 19 | -2426800117504 |
| 20 | 5346409013164 |
| 21 | -11558035326944 |
[1,-248,4124,-34752,213126,-1057504,4530744, -17333248,60655377,-197230000,603096260, -1749556736,4848776870,-12908659008,33161242504, -82505707520,199429765972,-469556091240, 1079330385764,-2426800117504,5346409013164, -11558035326944] |