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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -3 |
| 3 | 2 |
| 4 | 12 |
| 5 | -24 |
| 6 | 6 |
| 7 | -60 |
| 8 | 280 |
| 9 | -180 |
| 10 | 24 |
| 11 | 360 |
| 12 | -3600 |
| 13 | 4500 |
| 14 | -1440 |
| 15 | 120 |
| 16 | -2520 |
| 17 | 52080 |
| 18 | -113400 |
| 19 | 65520 |
| 20 | -12600 |
| 21 | 720 |
| 22 | 20160 |
| 23 | -846720 |
| 24 | 3034080 |
| 25 | -2822400 |
| 26 | 940800 |
| 27 | -120960 |
| 28 | 5040 |
| 29 | -181440 |
| 30 | 15361920 |
| 31 | -87635520 |
| 32 | 123451776 |
| 33 | -63504000 |
| 34 | 13789440 |
| 35 | -1270080 |
| 36 | 40320 |
[1,-3,2,12,-24,6,-60,280,-180,24,360,-3600,4500, -1440,120,-2520,52080,-113400,65520,-12600,720, 20160,-846720,3034080,-2822400,940800,-120960, 5040,-181440,15361920,-87635520,123451776, -63504000,13789440,-1270080,40320] |