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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 81 |
| 3 | 126 |
| 4 | 324 |
| 5 | 828 |
| 6 | 2124 |
| 7 | 5436 |
| 8 | 13932 |
| 9 | 35676 |
| 10 | 91404 |
| 11 | 234108 |
| 12 | 599724 |
| 13 | 1536156 |
| 14 | 3935052 |
| 15 | 10079676 |
| 16 | 25819884 |
| 17 | 66138588 |
| 18 | 169418124 |
| 19 | 433972476 |
| 20 | 1111644972 |
| 21 | 2847534876 |
| 22 | 7294114764 |
| 23 | 18684254268 |
| 24 | 47860713324 |
| 25 | 122597730396 |
| 26 | 314040583692 |
[9,81,126,324,828,2124,5436,13932,35676,91404, 234108,599724,1536156,3935052,10079676,25819884, 66138588,169418124,433972476,1111644972, 2847534876,7294114764,18684254268,47860713324, 122597730396,314040583692] |