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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 14 |
| 4 | 86 |
| 5 | 666 |
| 6 | 6418 |
| 7 | 64079 |
| 8 | 597445 |
| 9 | 5116146 |
| 10 | 40671872 |
| 11 | 304752986 |
| 12 | 2187716324 |
| 13 | 15395364971 |
| 14 | 110611591118 |
| 15 | 866239098731 |
| 16 | 7907500662596 |
[1,3,14,86,666,6418,64079,597445,5116146,40671872, 304752986,2187716324,15395364971,110611591118, 866239098731,7907500662596] |