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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 121 |
| 5 | 589 |
| 6 | 2821 |
| 7 | 13565 |
| 8 | 64661 |
| 9 | 308981 |
| 10 | 1468313 |
| 11 | 6989025 |
| 12 | 33140457 |
| 13 | 157329085 |
| 14 | 744818613 |
| 15 | 3529191009 |
| 16 | 16686979329 |
| 17 | 78955042017 |
| 18 | 372953947349 |
| 19 | 1762672203269 |
| 20 | 8319554639789 |
| 21 | 39285015083693 |
| 22 | 185296997240401 |
| 23 | 874331369198569 |
[1,5,25,121,589,2821,13565,64661,308981,1468313, 6989025,33140457,157329085,744818613,3529191009, 16686979329,78955042017,372953947349, 1762672203269,8319554639789,39285015083693, 185296997240401,874331369198569] |