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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 35 |
| 5 | 182 |
| 6 | 921 |
| 7 | 5062 |
| 8 | 28234 |
| 9 | 162330 |
| 10 | 947773 |
| 11 | 5622641 |
| 12 | 33747694 |
| 13 | 204676547 |
| 14 | 1252083028 |
| 15 | 7717376754 |
| 16 | 47878314072 |
| 17 | 298749048454 |
| 18 | 1873637869199 |
| 19 | 11804288518884 |
| 20 | 74673607921030 |
| 21 | 474128308291896 |
| 22 | 3020493580980524 |
| 23 | 19301224674496592 |
| 24 | 123681469340775568 |
[1,1,2,9,35,182,921,5062,28234,162330,947773, 5622641,33747694,204676547,1252083028,7717376754, 47878314072,298749048454,1873637869199, 11804288518884,74673607921030,474128308291896, 3020493580980524,19301224674496592, 123681469340775568] |