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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 3 |
| 3 | -21 |
| 4 | 180 |
| 5 | -1728 |
| 6 | 17766 |
| 7 | -191322 |
| 8 | 2130381 |
| 9 | -24328755 |
| 10 | 283378095 |
| 11 | -3353616513 |
| 12 | 40209584220 |
| 13 | -487400777388 |
| 14 | 5963013401400 |
| 15 | -73536394960872 |
| 16 | 913148848213740 |
| 17 | -11408099402698488 |
| 18 | 143288658075653370 |
| 19 | -1808347110471143550 |
| 20 | 22919638640740373070 |
| 21 | -291612557490911415990 |
| 22 | 3723227753617063771380 |
| 23 | -47688275868038913956940 |
| 24 | 612581097400862637697650 |
| 25 | -7889900533870136800820958 |
[1,-1,3,-21,180,-1728,17766,-191322,2130381, -24328755,283378095,-3353616513,40209584220, -487400777388,5963013401400,-73536394960872, 913148848213740,-11408099402698488, 143288658075653370,-1808347110471143550, 22919638640740373070,-291612557490911415990, 3723227753617063771380,-47688275868038913956940, 612581097400862637697650, -7889900533870136800820958] |