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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 63 |
| 5 | 326 |
| 6 | 1761 |
| 7 | 9808 |
| 8 | 55895 |
| 9 | 324301 |
| 10 | 1908878 |
| 11 | 11369744 |
| 12 | 68395917 |
| 13 | 414927215 |
| 14 | 2535523154 |
| 15 | 15592255913 |
| 16 | 96419104103 |
| 17 | 599176447614 |
| 18 | 3739845108057 |
| 19 | 23435007764606 |
| 20 | 147374772979438 |
| 21 | 929790132901804 |
| 22 | 5883377105975922 |
| 23 | 37328490926964481 |
| 24 | 237427707464042693 |
[1,3,13,63,326,1761,9808,55895,324301,1908878, 11369744,68395917,414927215,2535523154, 15592255913,96419104103,599176447614, 3739845108057,23435007764606,147374772979438, 929790132901804,5883377105975922, 37328490926964481,237427707464042693] |