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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | -3 |
| 5 | 0 |
| 6 | -90 |
| 7 | 168 |
| 8 | -4095 |
| 9 | 22176 |
| 10 | -291564 |
| 11 | 2834480 |
| 12 | -31372803 |
| 13 | 415999584 |
| 14 | -4743336598 |
| 15 | 72640890840 |
| 16 | -927946226207 |
| 17 | 15092982705088 |
| 18 | -219492662105272 |
| 19 | 3666238685959392 |
| 20 | -59492414408303971 |
[1,0,0,0,-3,0,-90,168,-4095,22176,-291564,2834480, -31372803,415999584,-4743336598,72640890840, -927946226207,15092982705088,-219492662105272, 3666238685959392,-59492414408303971] |