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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 18 |
| 4 | 410 |
| 5 | 18708 |
| 6 | 2894405 |
| 7 | 990192011 |
| 8 | 1043072889128 |
| 9 | 2618513670862020 |
| 10 | 19025225311119314543 |
| 11 | 345763553584576198026139 |
[1,3,18,410,18708,2894405,990192011,1043072889128, 2618513670862020,19025225311119314543, 345763553584576198026139] |