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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 3 |
| 5 | 3 |
| 6 | 8 |
| 7 | 16 |
| 8 | 32 |
| 9 | 70 |
| 10 | 135 |
| 11 | 293 |
| 12 | 585 |
| 13 | 1221 |
| 14 | 2496 |
| 15 | 5156 |
| 16 | 10609 |
| 17 | 21818 |
| 18 | 44955 |
| 19 | 92476 |
| 20 | 190459 |
| 21 | 391929 |
| 22 | 806935 |
| 23 | 1660946 |
| 24 | 3419147 |
| 25 | 7038323 |
| 26 | 14488296 |
| 27 | 29824518 |
| 28 | 61393333 |
| 29 | 126379174 |
| 30 | 260151058 |
| 31 | 535522942 |
| 32 | 1102374986 |
| 33 | 2269243610 |
| 34 | 4671246404 |
[0,1,0,3,3,8,16,32,70,135,293,585,1221,2496,5156, 10609,21818,44955,92476,190459,391929,806935, 1660946,3419147,7038323,14488296,29824518, 61393333,126379174,260151058,535522942,1102374986, 2269243610,4671246404] |