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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 57 |
| 4 | 1233 |
| 5 | 75393 |
| 6 | 19109889 |
| 7 | 6326835201 |
| 8 | 6388287561729 |
| 9 | 23576681450405889 |
| 10 | 120906321631678693377 |
| 11 | 1968421511613895105052673 |
| 12 | 111055505036706392268074909697 |
| 13 | 8965464105556083354144035638870017 |
[1,3,57,1233,75393,19109889,6326835201, 6388287561729,23576681450405889, 120906321631678693377,1968421511613895105052673, 111055505036706392268074909697, 8965464105556083354144035638870017] |