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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 13 |
| 4 | 27 |
| 5 | 62 |
| 6 | 135 |
| 7 | 312 |
| 8 | 825 |
| 9 | 2367 |
| 10 | 6940 |
| 11 | 21330 |
| 12 | 67814 |
| 13 | 216690 |
| 14 | 699884 |
| 15 | 2279373 |
| 16 | 7427118 |
| 17 | 24244543 |
| 18 | 79292187 |
| 19 | 259332414 |
| 20 | 848386032 |
| 21 | 2776599349 |
| 22 | 9087224618 |
| 23 | 29741257114 |
| 24 | 97348224464 |
| 25 | 318637326698 |
| 26 | 1042951906150 |
| 27 | 3413821643656 |
[3,9,13,27,62,135,312,825,2367,6940,21330,67814, 216690,699884,2279373,7427118,24244543,79292187, 259332414,848386032,2776599349,9087224618, 29741257114,97348224464,318637326698, 1042951906150,3413821643656] |