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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 8 |
| 3 | 25 |
| 4 | 81 |
| 5 | 263 |
| 6 | 855 |
| 7 | 2778 |
| 8 | 9027 |
| 9 | 29333 |
| 10 | 95316 |
| 11 | 309725 |
| 12 | 1006437 |
| 13 | 3270370 |
| 14 | 10626915 |
| 15 | 34531665 |
| 16 | 112209036 |
| 17 | 364618033 |
| 18 | 1184809305 |
| 19 | 3849982618 |
| 20 | 12510339087 |
| 21 | 40651763813 |
| 22 | 132096011916 |
| 23 | 429239834325 |
| 24 | 1394794836717 |
| 25 | 4532320816850 |
[2,8,25,81,263,855,2778,9027,29333,95316,309725, 1006437,3270370,10626915,34531665,112209036, 364618033,1184809305,3849982618,12510339087, 40651763813,132096011916,429239834325, 1394794836717,4532320816850] |