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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 312 |
| 4 | 31187 |
| 5 | 17438702 |
| 6 | 40575832476 |
| 7 | 404139015237875 |
| 8 | 17253201646564115439 |
| 9 | 3185118492387669085270268 |
| 10 | 2540927098290913247876202007100 |
[1,12,312,31187,17438702,40575832476, 404139015237875,17253201646564115439, 3185118492387669085270268, 2540927098290913247876202007100] |