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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 24 |
| 4 | 98 |
| 5 | 461 |
| 6 | 2458 |
| 7 | 14613 |
| 8 | 95461 |
| 9 | 677729 |
| 10 | 5184135 |
| 11 | 42428781 |
| 12 | 369422957 |
| 13 | 3405529609 |
| 14 | 33103337716 |
| 15 | 338110552799 |
[2,7,24,98,461,2458,14613,95461,677729,5184135, 42428781,369422957,3405529609,33103337716, 338110552799] |