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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 43 |
| 3 | 660 |
| 4 | 8834 |
| 5 | 110452 |
| 6 | 1325746 |
| 7 | 15469935 |
| 8 | 176818558 |
| 9 | 1989376733 |
| 10 | 22105676071 |
| 11 | 243175818741 |
[1,43,660,8834,110452,1325746,15469935,176818558, 1989376733,22105676071,243175818741] |