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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 27 |
| 4 | 75 |
| 5 | 201 |
| 6 | 525 |
| 7 | 1347 |
| 8 | 3411 |
| 9 | 8553 |
| 10 | 21285 |
| 11 | 52659 |
| 12 | 129675 |
| 13 | 318153 |
| 14 | 778269 |
| 15 | 1899267 |
| 16 | 4625955 |
| 17 | 11249481 |
| 18 | 27321525 |
| 19 | 66285747 |
| 20 | 160679451 |
| 21 | 389217513 |
| 22 | 942260205 |
| 23 | 2280029379 |
| 24 | 5514901875 |
| 25 | 13334998953 |
| 26 | 32235231429 |
| 27 | 77906125107 |
[3,9,27,75,201,525,1347,3411,8553,21285,52659, 129675,318153,778269,1899267,4625955,11249481, 27321525,66285747,160679451,389217513,942260205, 2280029379,5514901875,13334998953,32235231429, 77906125107] |