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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 10 |
| 3 | 52 |
| 4 | 444 |
| 5 | 3054 |
| 6 | 25814 |
| 7 | 192280 |
| 8 | 1557104 |
| 9 | 12157838 |
| 10 | 97030120 |
| 11 | 768491618 |
[0,10,52,444,3054,25814,192280,1557104,12157838, 97030120,768491618] |