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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 2 |
| 3 | 2 |
| 4 | 5 |
| 5 | 11 |
| 6 | 18 |
| 7 | 36 |
| 8 | 84 |
| 9 | 155 |
| 10 | 305 |
| 11 | 625 |
| 12 | 1269 |
| 13 | 2487 |
| 14 | 5070 |
| 15 | 10263 |
| 16 | 20964 |
| 17 | 41905 |
| 18 | 84799 |
| 19 | 170540 |
| 20 | 346192 |
| 21 | 696157 |
| 22 | 1405156 |
| 23 | 2822998 |
| 24 | 5686402 |
| 25 | 11420892 |
| 26 | 22949684 |
| 27 | 46028648 |
| 28 | 92347798 |
| 29 | 185051670 |
| 30 | 370756866 |
| 31 | 742307736 |
| 32 | 1485798060 |
| 33 | 2972924906 |
| 34 | 5947567564 |
[1,0,2,2,5,11,18,36,84,155,305,625,1269,2487,5070, 10263,20964,41905,84799,170540,346192,696157, 1405156,2822998,5686402,11420892,22949684, 46028648,92347798,185051670,370756866,742307736, 1485798060,2972924906,5947567564] |