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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 12 |
| 4 | 476 |
| 5 | 11460 |
| 6 | 1881856 |
| 7 | 1009387819 |
| 8 | 1201130067486 |
| 9 | 5391490611757566 |
[1,4,12,476,11460,1881856,1009387819, 1201130067486,5391490611757566] |