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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 16 |
| 4 | 84 |
| 5 | 458 |
| 6 | 2541 |
| 7 | 14286 |
| 8 | 81103 |
| 9 | 463913 |
| 10 | 2669576 |
| 11 | 15437366 |
| 12 | 89633392 |
| 13 | 522223740 |
| 14 | 3051529665 |
| 15 | 17876415654 |
| 16 | 104955553899 |
| 17 | 617415739622 |
| 18 | 3638327064022 |
| 19 | 21473223755896 |
| 20 | 126910074421985 |
| 21 | 751000070996514 |
| 22 | 4449166010804565 |
| 23 | 26385683227918794 |
| 24 | 156628589801790627 |
[1,3,16,84,458,2541,14286,81103,463913,2669576, 15437366,89633392,522223740,3051529665, 17876415654,104955553899,617415739622, 3638327064022,21473223755896,126910074421985, 751000070996514,4449166010804565, 26385683227918794,156628589801790627] |