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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | -1 |
| 2 | 0 |
| 3 | -2 |
| 4 | 8 |
| 5 | -86 |
| 6 | 1448 |
| 7 | -40608 |
| 8 | 1867080 |
| 9 | -140055600 |
| 10 | 17085644400 |
| 11 | -3383043446640 |
| 12 | 1085946439923840 |
| 13 | -564694233102890880 |
| 14 | 475471874409018791040 |
| 15 | -648068513405723438730240 |
| 16 | 1429638846930684965104992000 |
| 17 | -5103811083889432701541321459200 |
[0,-1,0,-2,8,-86,1448,-40608,1867080,-140055600, 17085644400,-3383043446640,1085946439923840, -564694233102890880,475471874409018791040, -648068513405723438730240, 1429638846930684965104992000, -5103811083889432701541321459200] |