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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 15 |
| 3 | 55 |
| 4 | 131 |
| 5 | 163 |
| 6 | -169 |
| 7 | -1521 |
| 8 | -4437 |
| 9 | -7429 |
| 10 | -2945 |
| 11 | 26471 |
| 12 | 101587 |
| 13 | 207699 |
| 14 | 201639 |
| 15 | -306497 |
| 16 | -1907461 |
| 17 | -4718165 |
| 18 | -6464305 |
| 19 | 547863 |
| 20 | 30463779 |
| 21 | 93816323 |
| 22 | 161591287 |
| 23 | 97035119 |
| 24 | -400669877 |
| 25 | -1676486565 |
| 26 | -3504149217 |
| 27 | -3693262649 |
[1,3,15,55,131,163,-169,-1521,-4437,-7429,-2945, 26471,101587,207699,201639,-306497,-1907461, -4718165,-6464305,547863,30463779,93816323, 161591287,97035119,-400669877,-1676486565, -3504149217,-3693262649] |