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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 196 |
| 4 | 6084 |
| 5 | 219024 |
| 6 | 8450649 |
| 7 | 338265664 |
| 8 | 13840346025 |
| 9 | 574510941225 |
| 10 | 24093764931600 |
[1,9,196,6084,219024,8450649,338265664, 13840346025,574510941225,24093764931600] |