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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -9 |
| 2 | 54 |
| 3 | -45 |
| 4 | -1404 |
| 5 | 6264 |
| 6 | 1890 |
| 7 | -76050 |
| 8 | 187272 |
| 9 | -8865 |
| 10 | -1540944 |
| 11 | 6200280 |
| 12 | -1621620 |
| 13 | -51195330 |
| 14 | 109055700 |
| 15 | 42125400 |
| 16 | -868685040 |
| 17 | 2946297888 |
| 18 | 74093670 |
| 19 | -21584605122 |
| 20 | 44912353824 |
| 21 | -17376284250 |
| 22 | -302040439920 |
| 23 | 1069478852112 |
| 24 | 249392931480 |
| 25 | -7095191496489 |
[1,-9,54,-45,-1404,6264,1890,-76050,187272,-8865, -1540944,6200280,-1621620,-51195330,109055700, 42125400,-868685040,2946297888,74093670, -21584605122,44912353824,-17376284250, -302040439920,1069478852112,249392931480, -7095191496489] |