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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | -2 |
| 8 | 6 |
| 9 | -21 |
| 10 | 77 |
| 11 | -308 |
| 12 | 1326 |
| 13 | -6159 |
| 14 | 30691 |
| 15 | -163262 |
| 16 | 923364 |
| 17 | -5532187 |
| 18 | 34999420 |
| 19 | -233141556 |
| 20 | 1631008138 |
| 21 | -11955337672 |
| 22 | 91626679088 |
| 23 | -732828332694 |
| 24 | 6105747679463 |
| 25 | -52908981009168 |
| 26 | 476130261273006 |
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