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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 28 |
| 4 | 905 |
| 5 | 103126 |
| 6 | 43437282 |
| 7 | 66141208960 |
| 8 | 385335180349569 |
| 9 | 8212830157184175946 |
| 10 | 683805150345009276656138 |
| 11 | 209730232681034628698652412600 |
| 12 | 254785524744054762580308183579130562 |
[1,3,28,905,103126,43437282,66141208960, 385335180349569,8212830157184175946, 683805150345009276656138, 209730232681034628698652412600, 254785524744054762580308183579130562] |