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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 2 |
| 3 | 0 |
| 4 | -2 |
| 5 | 4 |
| 6 | -2 |
| 7 | 0 |
| 8 | 6 |
| 9 | -4 |
| 10 | 6 |
| 11 | 8 |
| 12 | -2 |
| 13 | 20 |
| 14 | 14 |
| 15 | 16 |
| 16 | 54 |
| 17 | 44 |
| 18 | 86 |
| 19 | 152 |
| 20 | 174 |
| 21 | 324 |
| 22 | 478 |
| 23 | 672 |
| 24 | 1126 |
| 25 | 1628 |
| 26 | 2470 |
| 27 | 3880 |
| 28 | 5726 |
| 29 | 8820 |
| 30 | 13486 |
| 31 | 20272 |
| 32 | 31126 |
| 33 | 47244 |
| 34 | 71670 |
| 35 | 109496 |
| 36 | 166158 |
| 37 | 252836 |
| 38 | 385150 |
| 39 | 585152 |
[1,-2,2,0,-2,4,-2,0,6,-4,6,8,-2,20,14,16,54,44,86, 152,174,324,478,672,1126,1628,2470,3880,5726,8820, 13486,20272,31126,47244,71670,109496,166158, 252836,385150,585152] |