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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 15 |
| 6 | 39 |
| 7 | 133 |
| 8 | 511 |
| 9 | 2773 |
| 10 | 14873 |
| 11 | 106373 |
| 12 | 810293 |
| 13 | 8275081 |
| 14 | 88902809 |
| 15 | 1280398135 |
| 16 | 19384764865 |
| 17 | 392921704943 |
| 18 | 8381650583597 |
| 19 | 239524090999801 |
| 20 | 7208159770278487 |
| 21 | 290528855860261289 |
| 22 | 12317566856380616673 |
[1,1,3,5,15,39,133,511,2773,14873,106373,810293, 8275081,88902809,1280398135,19384764865, 392921704943,8381650583597,239524090999801, 7208159770278487,290528855860261289, 12317566856380616673] |