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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 12 |
| 3 | 271 |
| 4 | 24950 |
| 5 | 9800058 |
| 6 | 16942485560 |
| 7 | 131898088386405 |
| 8 | 4704783844260626244 |
[2,12,271,24950,9800058,16942485560, 131898088386405,4704783844260626244] |