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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 37 |
| 3 | 556 |
| 4 | 9107 |
| 5 | 172904 |
| 6 | 2890017 |
| 7 | 49684593 |
| 8 | 821323042 |
| 9 | 13475380990 |
[1,37,556,9107,172904,2890017,49684593,821323042, 13475380990] |