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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 39 |
| 5 | 201 |
| 6 | 1227 |
| 7 | 8305 |
| 8 | 61383 |
| 9 | 487761 |
| 10 | 4131819 |
| 11 | 37072361 |
| 12 | 350644047 |
| 13 | 3482957945 |
| 14 | 36220558835 |
| 15 | 393329507169 |
| 16 | 4450157382383 |
| 17 | 52354044069009 |
| 18 | 639307054297779 |
| 19 | 8090092395577625 |
| 20 | 105935581968131399 |
| 21 | 1433456549698679385 |
| 22 | 20018656224312123051 |
[0,1,3,9,39,201,1227,8305,61383,487761,4131819, 37072361,350644047,3482957945,36220558835, 393329507169,4450157382383,52354044069009, 639307054297779,8090092395577625, 105935581968131399,1433456549698679385, 20018656224312123051] |