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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | -1 |
| 4 | -3 |
| 5 | -7 |
| 6 | -14 |
| 7 | -25 |
| 8 | -41 |
| 9 | -64 |
| 10 | -100 |
| 11 | -165 |
| 12 | -294 |
| 13 | -550 |
| 14 | -1023 |
| 15 | -1795 |
| 16 | -2823 |
| 17 | -3658 |
| 18 | -2882 |
| 19 | 2873 |
| 20 | 20435 |
| 21 | 62185 |
| 22 | 148863 |
| 23 | 314008 |
| 24 | 613957 |
| 25 | 1155794 |
| 26 | 2175823 |
| 27 | 4244026 |
| 28 | 8753538 |
| 29 | 19006490 |
| 30 | 42471787 |
| 31 | 95234575 |
| 32 | 210395407 |
| 33 | 453413866 |
| 34 | 949508390 |
| 35 | 1931939460 |
[1,0,0,-1,-3,-7,-14,-25,-41,-64,-100,-165,-294, -550,-1023,-1795,-2823,-3658,-2882,2873,20435, 62185,148863,314008,613957,1155794,2175823, 4244026,8753538,19006490,42471787,95234575, 210395407,453413866,949508390,1931939460] |