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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 27 |
| 4 | 83 |
| 5 | 263 |
| 6 | 855 |
| 7 | 2723 |
| 8 | 8731 |
| 9 | 27999 |
| 10 | 89663 |
| 11 | 287355 |
| 12 | 920771 |
| 13 | 2950263 |
| 14 | 9453607 |
| 15 | 30291667 |
| 16 | 97062123 |
| 17 | 311012623 |
| 18 | 996563855 |
| 19 | 3193247403 |
| 20 | 10231988371 |
| 21 | 32785923879 |
| 22 | 105054547063 |
| 23 | 336621829635 |
| 24 | 1078623042491 |
| 25 | 3456186066623 |
| 26 | 11074510391007 |
| 27 | 35485583833307 |
[1,3,7,27,83,263,855,2723,8731,27999,89663,287355, 920771,2950263,9453607,30291667,97062123, 311012623,996563855,3193247403,10231988371, 32785923879,105054547063,336621829635, 1078623042491,3456186066623,11074510391007, 35485583833307] |