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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | -1 |
| 3 | -78 |
| 4 | 880 |
| 5 | -4656 |
| 6 | -14304 |
| 7 | -423936 |
| 8 | 8342720 |
| 9 | 711956736 |
| 10 | -615707136 |
| 11 | 21057138688 |
| 12 | -4663930678272 |
| 13 | 211912980656128 |
| 14 | -9178450735677440 |
| 15 | 40005919124799488 |
| 16 | 83013253447139328 |
| 17 | -8525111273818357760 |
| 18 | -800258888289188708352 |
| 19 | -15170733077495639179264 |
[2,-1,-78,880,-4656,-14304,-423936,8342720, 711956736,-615707136,21057138688,-4663930678272, 211912980656128,-9178450735677440, 40005919124799488,83013253447139328, -8525111273818357760,-800258888289188708352, -15170733077495639179264] |