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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 36 |
| 5 | 324 |
| 6 | 7041 |
| 7 | 233265 |
| 8 | 16038658 |
| 9 | 1884307184 |
| 10 | 426645198097 |
| 11 | 173238487743952 |
[1,2,5,36,324,7041,233265,16038658,1884307184, 426645198097,173238487743952] |