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| n | a(n) |
|---|---|
| 1 | -1 |
| 2 | 0 |
| 3 | 3 |
| 4 | -5 |
| 5 | -3 |
| 6 | 26 |
| 7 | -35 |
| 8 | -48 |
| 9 | 245 |
| 10 | -248 |
| 11 | -639 |
| 12 | 2355 |
| 13 | -1573 |
| 14 | -7890 |
| 15 | 22555 |
| 16 | -6685 |
| 17 | -93075 |
| 18 | 212280 |
| 19 | 27625 |
| 20 | -1061415 |
| 21 | 1938855 |
| 22 | 1276550 |
| 23 | -11763465 |
| 24 | 16906450 |
| 25 | 23324507 |
| 26 | -126971664 |
| 27 | 136840575 |
| 28 | 343314517 |
| 29 | -1334857995 |
| 30 | 965192298 |
[-1,0,3,-5,-3,26,-35,-48,245,-248,-639,2355,-1573, -7890,22555,-6685,-93075,212280,27625,-1061415, 1938855,1276550,-11763465,16906450,23324507, -126971664,136840575,343314517,-1334857995, 965192298] |