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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 140 |
| 5 | 10563 |
| 6 | 2098813 |
| 7 | 1097286743 |
| 8 | 1507709268026 |
| 9 | 5360839557388973 |
| 10 | 49384396585140778697 |
[1,2,8,140,10563,2098813,1097286743,1507709268026, 5360839557388973,49384396585140778697] |