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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 14 |
| 6 | 150 |
| 7 | 18406 |
| 8 | 311742406 |
| 9 | 96402927697811206 |
| 10 | 9292975819514867485089851568784006 |
[1,1,2,4,14,150,18406,311742406,96402927697811206, 9292975819514867485089851568784006] |