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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 15 |
| 6 | 51 |
| 7 | 52 |
| 8 | 267 |
| 9 | 2328 |
| 10 | 56092 |
| 11 | 10494213 |
| 12 | 49487367289 |
[1,2,5,14,15,51,52,267,2328,56092,10494213, 49487367289] |