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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 13 |
| 4 | 27 |
| 5 | 60 |
| 6 | 123 |
| 7 | 280 |
| 8 | 729 |
| 9 | 2015 |
| 10 | 5844 |
| 11 | 17796 |
| 12 | 55746 |
| 13 | 176718 |
| 14 | 565998 |
| 15 | 1824691 |
| 16 | 5895378 |
| 17 | 19079961 |
| 18 | 61831121 |
| 19 | 200450950 |
| 20 | 650016786 |
| 21 | 2108377349 |
| 22 | 6839182152 |
| 23 | 22185876476 |
| 24 | 71972913726 |
| 25 | 233489826816 |
| 26 | 757476164734 |
| 27 | 2457387441714 |
[3,9,13,27,60,123,280,729,2015,5844,17796,55746, 176718,565998,1824691,5895378,19079961,61831121, 200450950,650016786,2108377349,6839182152, 22185876476,71972913726,233489826816,757476164734, 2457387441714] |