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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 3 |
| 6 | 6 |
| 7 | 11 |
| 8 | 22 |
| 9 | 42 |
| 10 | 81 |
| 11 | 156 |
| 12 | 301 |
| 13 | 580 |
| 14 | 1118 |
| 15 | 2155 |
| 16 | 4154 |
| 17 | 8007 |
| 18 | 15434 |
| 19 | 29750 |
| 20 | 57345 |
| 21 | 110536 |
| 22 | 213065 |
| 23 | 410696 |
| 24 | 791642 |
| 25 | 1525939 |
| 26 | 2941342 |
| 27 | 5669619 |
| 28 | 10928542 |
| 29 | 21065442 |
| 30 | 40604945 |
| 31 | 78268548 |
| 32 | 150867477 |
| 33 | 290806412 |
| 34 | 560547382 |
| 35 | 1080489819 |
[1,0,1,0,2,3,6,11,22,42,81,156,301,580,1118,2155, 4154,8007,15434,29750,57345,110536,213065,410696, 791642,1525939,2941342,5669619,10928542,21065442, 40604945,78268548,150867477,290806412,560547382, 1080489819] |