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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | -1 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 1 |
| 9 | 2 |
| 10 | 4 |
| 11 | 8 |
| 12 | 13 |
| 13 | 22 |
| 14 | 38 |
| 15 | 68 |
| 16 | 125 |
| 17 | 232 |
| 18 | 429 |
| 19 | 786 |
| 20 | 1428 |
| 21 | 2578 |
| 22 | 4645 |
| 23 | 8364 |
| 24 | 15064 |
| 25 | 27145 |
| 26 | 48990 |
| 27 | 88736 |
| 28 | 161813 |
| 29 | 298001 |
| 30 | 555451 |
| 31 | 1048207 |
| 32 | 1999608 |
| 33 | 3844722 |
| 34 | 7425094 |
| 35 | 14356699 |
| 36 | 27722560 |
| 37 | 53374986 |
[0,0,-1,0,0,0,0,1,2,4,8,13,22,38,68,125,232,429, 786,1428,2578,4645,8364,15064,27145,48990,88736, 161813,298001,555451,1048207,1999608,3844722, 7425094,14356699,27722560,53374986] |