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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 116 |
| 4 | 3652 |
| 5 | 285704 |
| 6 | 61946920 |
| 7 | 33736398032 |
| 8 | 51083363186704 |
| 9 | 194585754101247008 |
| 10 | 2061787082699360148640 |
| 11 | 54969782721182164414355264 |
[1,2,10,116,3652,285704,61946920,33736398032, 51083363186704,194585754101247008, 2061787082699360148640,54969782721182164414355264] |