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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -30 |
| 2 | 435 |
| 3 | -4090 |
| 4 | 28305 |
| 5 | -155586 |
| 6 | 716910 |
| 7 | -2884080 |
| 8 | 10440930 |
| 9 | -34752790 |
| 10 | 107952705 |
| 11 | -316326840 |
| 12 | 881621260 |
| 13 | -2352438330 |
| 14 | 6041102175 |
| 15 | -14993771926 |
| 16 | 36092874960 |
| 17 | -84513784620 |
| 18 | 192981056950 |
| 19 | -430636738770 |
| 20 | 940848408276 |
[1,-30,435,-4090,28305,-155586,716910,-2884080, 10440930,-34752790,107952705,-316326840,881621260, -2352438330,6041102175,-14993771926,36092874960, -84513784620,192981056950,-430636738770, 940848408276] |