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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 7 |
| 6 | 24 |
| 7 | 76 |
| 8 | 240 |
| 9 | 787 |
| 10 | 2670 |
| 11 | 9233 |
| 12 | 32293 |
| 13 | 114051 |
| 14 | 406588 |
| 15 | 1461748 |
| 16 | 5293301 |
| 17 | 19287242 |
| 18 | 70660178 |
| 19 | 260127781 |
| 20 | 961814451 |
| 21 | 3570265304 |
| 22 | 13299988867 |
| 23 | 49705359457 |
| 24 | 186309387918 |
| 25 | 700228153534 |
| 26 | 2638299418839 |
| 27 | 9963349661693 |
| 28 | 37705935306758 |
| 29 | 142978684267052 |
| 30 | 543164138444912 |
| 31 | 2066978553423647 |
| 32 | 7878398598991602 |
| 33 | 30074161433351617 |
| 34 | 114964340210315649 |
[1,1,1,2,7,24,76,240,787,2670,9233,32293,114051, 406588,1461748,5293301,19287242,70660178, 260127781,961814451,3570265304,13299988867, 49705359457,186309387918,700228153534, 2638299418839,9963349661693,37705935306758, 142978684267052,543164138444912,2066978553423647, 7878398598991602,30074161433351617, 114964340210315649] |