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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 7 |
| 5 | 20 |
| 6 | 35 |
| 7 | 83 |
| 8 | 161 |
| 9 | 355 |
| 10 | 720 |
| 11 | 1541 |
| 12 | 3185 |
| 13 | 6733 |
| 14 | 14027 |
| 15 | 29500 |
| 16 | 61663 |
| 17 | 129403 |
| 18 | 270865 |
| 19 | 567911 |
| 20 | 1189440 |
| 21 | 2492905 |
| 22 | 5222449 |
| 23 | 10943813 |
| 24 | 22928815 |
| 25 | 48044900 |
| 26 | 100665083 |
| 27 | 210927155 |
| 28 | 441948689 |
| 29 | 926020171 |
| 30 | 1940274000 |
| 31 | 4065458669 |
| 32 | 8518311809 |
[0,1,1,5,7,20,35,83,161,355,720,1541,3185,6733, 14027,29500,61663,129403,270865,567911,1189440, 2492905,5222449,10943813,22928815,48044900, 100665083,210927155,441948689,926020171, 1940274000,4065458669,8518311809] |