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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 7 |
| 7 | 13 |
| 8 | 42 |
| 9 | 62 |
| 10 | 81 |
| 11 | 68 |
| 12 | 130 |
| 13 | 135 |
| 14 | 648 |
| 15 | 1408 |
| 16 | 9418 |
| 17 | 17036 |
| 18 | 79261 |
| 19 | 87517 |
| 20 | 150946 |
| 21 | 736926 |
| 22 | 1350266 |
| 23 | 7899219 |
| 24 | 16380155 |
| 25 | 70858879 |
| 26 | 162124155 |
| 27 | 704415429 |
| 28 | 1573821475 |
| 29 | 7217219419 |
| 30 | 15814925285 |
| 31 | 73143352729 |
| 32 | 160127403115 |
[0,0,1,1,2,4,7,13,42,62,81,68,130,135,648,1408, 9418,17036,79261,87517,150946,736926,1350266, 7899219,16380155,70858879,162124155,704415429, 1573821475,7217219419,15814925285,73143352729, 160127403115] |