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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 26 |
| 3 | 91 |
| 4 | 316 |
| 5 | 1031 |
| 6 | 3354 |
| 7 | 10615 |
| 8 | 33344 |
| 9 | 103339 |
| 10 | 317958 |
| 11 | 970515 |
| 12 | 2945172 |
| 13 | 8888719 |
| 14 | 26705714 |
| 15 | 79909167 |
| 16 | 238257768 |
| 17 | 708129267 |
| 18 | 2098664158 |
| 19 | 6203795403 |
| 20 | 18296271036 |
| 21 | 53845375703 |
| 22 | 158159174410 |
| 23 | 463734769895 |
| 24 | 1357486034320 |
| 25 | 3967761581627 |
[7,26,91,316,1031,3354,10615,33344,103339,317958, 970515,2945172,8888719,26705714,79909167, 238257768,708129267,2098664158,6203795403, 18296271036,53845375703,158159174410,463734769895, 1357486034320,3967761581627] |