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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 19 |
| 3 | 101 |
| 4 | 409 |
| 5 | 1531 |
| 6 | 5507 |
| 7 | 19273 |
| 8 | 65677 |
| 9 | 220859 |
| 10 | 733559 |
| 11 | 2412763 |
| 12 | 7867543 |
| 13 | 25485179 |
| 14 | 82064011 |
| 15 | 262960069 |
| 16 | 839001707 |
| 17 | 2666790157 |
| 18 | 8448283721 |
| 19 | 26684834629 |
| 20 | 84064182049 |
| 21 | 264194301341 |
| 22 | 828513359543 |
| 23 | 2593131866471 |
| 24 | 8101615860581 |
| 25 | 25270000074743 |
[3,19,101,409,1531,5507,19273,65677,220859,733559, 2412763,7867543,25485179,82064011,262960069, 839001707,2666790157,8448283721,26684834629, 84064182049,264194301341,828513359543, 2593131866471,8101615860581,25270000074743] |