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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 3 |
| 5 | 5 |
| 6 | 5 |
| 7 | 10 |
| 8 | 10 |
| 9 | 24 |
| 10 | 24 |
| 11 | 66 |
| 12 | 66 |
| 13 | 198 |
| 14 | 198 |
| 15 | 627 |
| 16 | 627 |
| 17 | 2057 |
| 18 | 2057 |
| 19 | 6919 |
| 20 | 6919 |
| 21 | 23715 |
| 22 | 23715 |
| 23 | 82501 |
| 24 | 82501 |
| 25 | 290513 |
| 26 | 290513 |
| 27 | 1033413 |
| 28 | 1033413 |
| 29 | 3707853 |
| 30 | 3707853 |
| 31 | 13402698 |
| 32 | 13402698 |
| 33 | 48760368 |
| 34 | 48760368 |
| 35 | 178405158 |
| 36 | 178405158 |
| 37 | 656043858 |
[1,2,2,3,3,5,5,10,10,24,24,66,66,198,198,627,627, 2057,2057,6919,6919,23715,23715,82501,82501, 290513,290513,1033413,1033413,3707853,3707853, 13402698,13402698,48760368,48760368,178405158, 178405158,656043858] |