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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 15 |
| 5 | 81 |
| 6 | 123 |
| 7 | 279 |
| 8 | 945 |
| 9 | 1419 |
| 10 | 3195 |
| 11 | 7191 |
| 12 | 24273 |
| 13 | 36411 |
| 14 | 81927 |
| 15 | 276507 |
| 16 | 622143 |
| 17 | 7086609 |
| 18 | 10629915 |
| 19 | 23917311 |
| 20 | 612974547 |
| 21 | 1379192733 |
| 22 | 2068789101 |
| 23 | 3103183653 |
| 24 | 4654775481 |
| 25 | 6982163223 |
| 26 | 23564800881 |
| 27 | 35347201323 |
| 28 | 79531202979 |
| 29 | 178945206705 |
| 30 | 268417810059 |
[1,3,9,15,81,123,279,945,1419,3195,7191,24273, 36411,81927,276507,622143,7086609,10629915, 23917311,612974547,1379192733,2068789101, 3103183653,4654775481,6982163223,23564800881, 35347201323,79531202979,178945206705,268417810059] |