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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 2 |
| 5 | 7 |
| 6 | 15 |
| 7 | 35 |
| 8 | 75 |
| 9 | 163 |
| 10 | 337 |
| 11 | 709 |
| 12 | 1458 |
| 13 | 3001 |
| 14 | 6135 |
| 15 | 12529 |
| 16 | 25468 |
| 17 | 51739 |
| 18 | 104829 |
| 19 | 212205 |
| 20 | 428916 |
| 21 | 866215 |
| 22 | 1747527 |
| 23 | 3523213 |
| 24 | 7097895 |
| 25 | 14291683 |
| 26 | 28760643 |
| 27 | 57852469 |
| 28 | 116321445 |
| 29 | 233798623 |
| 30 | 469761015 |
| 31 | 943591237 |
| 32 | 1894836585 |
| 33 | 3804113881 |
| 34 | 7635493643 |
[0,0,0,1,2,7,15,35,75,163,337,709,1458,3001,6135, 12529,25468,51739,104829,212205,428916,866215, 1747527,3523213,7097895,14291683,28760643, 57852469,116321445,233798623,469761015,943591237, 1894836585,3804113881,7635493643] |