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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 15 |
| 4 | 3 |
| 5 | 2136 |
| 6 | 4 |
| 7 | 788244 |
| 8 | 7 |
| 9 | 73780392 |
| 10 | 6 |
| 11 | 57067140928 |
| 12 | 1361665032086 |
| 13 | 19953429852608 |
| 14 | 290660101635794 |
| 15 | 74896929428416952 |
| 16 | 24660071077535201 |
| 17 | 5620182896687887031 |
[1,2,15,3,2136,4,788244,7,73780392,6,57067140928, 1361665032086,19953429852608,290660101635794, 74896929428416952,24660071077535201, 5620182896687887031] |