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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 60 |
| 3 | 295 |
| 4 | 1970 |
| 5 | 12547 |
| 6 | 77426 |
| 7 | 490668 |
| 8 | 3078638 |
| 9 | 19343899 |
| 10 | 121656933 |
| 11 | 764438509 |
| 12 | 4805307635 |
| 13 | 30204033317 |
| 14 | 189843766164 |
| 15 | 1193281179607 |
| 16 | 7500358766425 |
| 17 | 47143616101848 |
| 18 | 296322172696548 |
| 19 | 1862536668117625 |
| 20 | 11707004939753233 |
[6,60,295,1970,12547,77426,490668,3078638, 19343899,121656933,764438509,4805307635, 30204033317,189843766164,1193281179607, 7500358766425,47143616101848,296322172696548, 1862536668117625,11707004939753233] |