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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 0 |
| 4 | -2 |
| 5 | 6 |
| 6 | -10 |
| 7 | 6 |
| 8 | 26 |
| 9 | -126 |
| 10 | 358 |
| 11 | -794 |
| 12 | 1452 |
| 13 | -2168 |
| 14 | 2450 |
| 15 | -1596 |
| 16 | -54 |
| 17 | -3352 |
| 18 | 35088 |
| 19 | -162676 |
| 20 | 551420 |
| 21 | -1561654 |
| 22 | 3913674 |
| 23 | -8958364 |
| 24 | 19130040 |
| 25 | -38763072 |
| 26 | 75704786 |
| 27 | -144660744 |
| 28 | 273998122 |
| 29 | -518406656 |
| 30 | 978530058 |
| 31 | -1819685864 |
| 32 | 3249902518 |
| 33 | -5326356342 |
| 34 | 7227494208 |
| 35 | -5082314876 |
[1,2,2,0,-2,6,-10,6,26,-126,358,-794,1452,-2168, 2450,-1596,-54,-3352,35088,-162676,551420, -1561654,3913674,-8958364,19130040,-38763072, 75704786,-144660744,273998122,-518406656, 978530058,-1819685864,3249902518,-5326356342, 7227494208,-5082314876] |