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| n | a(n) |
|---|---|
| 2 | 15 |
| 3 | 130 |
| 4 | 654 |
| 5 | 21114 |
| 6 | 4598780 |
| 7 | 245633790 |
| 8 | 5364544542 |
| 9 | 200916041330 |
[15,130,654,21114,4598780,245633790,5364544542, 200916041330] |