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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | -1 |
| 3 | 4 |
| 4 | -2 |
| 5 | -14 |
| 6 | 36 |
| 7 | -1 |
| 8 | -191 |
| 9 | 418 |
| 10 | 182 |
| 11 | -2904 |
| 12 | 5546 |
| 13 | 5226 |
| 14 | -47466 |
| 15 | 78843 |
| 16 | 121489 |
| 17 | -813060 |
| 18 | 1157400 |
| 19 | 2659695 |
| 20 | -14364997 |
| 21 | 17078752 |
| 22 | 56866292 |
| 23 | -259091498 |
| 24 | 246553176 |
| 25 | 1202210486 |
| 26 | -4736784794 |
| 27 | 3346401868 |
| 28 | 25255328948 |
| 29 | -87323306720 |
| 30 | 39123129700 |
[1,-1,-1,4,-2,-14,36,-1,-191,418,182,-2904,5546, 5226,-47466,78843,121489,-813060,1157400,2659695, -14364997,17078752,56866292,-259091498,246553176, 1202210486,-4736784794,3346401868,25255328948, -87323306720,39123129700] |