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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 2539 |
| 3 | 794416 |
| 4 | 316561994 |
| 5 | 117380324984 |
| 6 | 44832664800117 |
| 7 | 16925667317073175 |
[6,2539,794416,316561994,117380324984, 44832664800117,16925667317073175] |