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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 27 |
| 3 | 81 |
| 4 | 198 |
| 5 | 459 |
| 6 | 972 |
| 7 | 1989 |
| 8 | 3861 |
| 9 | 7290 |
| 10 | 13284 |
| 11 | 23679 |
| 12 | 41148 |
| 13 | 70218 |
| 14 | 117504 |
| 15 | 193671 |
| 16 | 314262 |
| 17 | 503415 |
| 18 | 796068 |
| 19 | 1244988 |
| 20 | 1925910 |
| 21 | 2950668 |
| 22 | 4478328 |
| 23 | 6739497 |
| 24 | 10059228 |
| 25 | 14901471 |
| 26 | 21914442 |
| 27 | 32011119 |
| 28 | 46456272 |
| 29 | 67010679 |
| 30 | 96093864 |
| 31 | 137039922 |
| 32 | 194395221 |
[1,9,27,81,198,459,972,1989,3861,7290,13284,23679, 41148,70218,117504,193671,314262,503415,796068, 1244988,1925910,2950668,4478328,6739497,10059228, 14901471,21914442,32011119,46456272,67010679, 96093864,137039922,194395221] |