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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 11 |
| 3 | 31 |
| 4 | 88 |
| 5 | 287 |
| 6 | 881 |
| 7 | 2686 |
| 8 | 8347 |
| 9 | 25763 |
| 10 | 79376 |
| 11 | 245227 |
| 12 | 757045 |
| 13 | 2336222 |
| 14 | 7212287 |
| 15 | 22263871 |
| 16 | 68722504 |
| 17 | 212138639 |
| 18 | 654844841 |
| 19 | 2021399374 |
| 20 | 6239772643 |
| 21 | 19261292171 |
| 22 | 59456768000 |
| 23 | 183534426499 |
| 24 | 566544237805 |
| 25 | 1748839677662 |
| 26 | 5398414303799 |
[2,11,31,88,287,881,2686,8347,25763,79376,245227, 757045,2336222,7212287,22263871,68722504, 212138639,654844841,2021399374,6239772643, 19261292171,59456768000,183534426499,566544237805, 1748839677662,5398414303799] |