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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -30 |
| 2 | 405 |
| 3 | -3250 |
| 4 | 17460 |
| 5 | -69456 |
| 6 | 237485 |
| 7 | -817830 |
| 8 | 2827605 |
| 9 | -8867120 |
| 10 | 25403229 |
| 11 | -73380060 |
| 12 | 215448665 |
| 13 | -595626330 |
| 14 | 1559581965 |
| 15 | -4136899912 |
| 16 | 11020769280 |
| 17 | -28085275230 |
| 18 | 69659708200 |
| 19 | -174426721890 |
| 20 | 433560026502 |
[1,-30,405,-3250,17460,-69456,237485,-817830, 2827605,-8867120,25403229,-73380060,215448665, -595626330,1559581965,-4136899912,11020769280, -28085275230,69659708200,-174426721890, 433560026502] |