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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 27 |
| 4 | 79 |
| 5 | 229 |
| 6 | 659 |
| 7 | 1889 |
| 8 | 5401 |
| 9 | 15419 |
| 10 | 43977 |
| 11 | 125355 |
| 12 | 357191 |
| 13 | 1017565 |
| 14 | 2898435 |
| 15 | 8255201 |
| 16 | 23510865 |
| 17 | 66956883 |
| 18 | 190683433 |
| 19 | 543031707 |
| 20 | 1546443295 |
| 21 | 4403932917 |
| 22 | 12541401683 |
| 23 | 35714999425 |
| 24 | 101707905961 |
| 25 | 289639951179 |
| 26 | 824825396777 |
[3,9,27,79,229,659,1889,5401,15419,43977,125355, 357191,1017565,2898435,8255201,23510865,66956883, 190683433,543031707,1546443295,4403932917, 12541401683,35714999425,101707905961,289639951179, 824825396777] |