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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 11 |
| 3 | 457 |
| 4 | 3251 |
| 5 | 165701 |
| 6 | 10526557 |
| 7 | 495233351 |
| 8 | 196039655873 |
| 9 | 10687033762033 |
| 10 | 79006533276941 |
| 11 | 4313367040646743 |
| 12 | 1740318019946551931 |
[2,11,457,3251,165701,10526557,495233351, 196039655873,10687033762033,79006533276941, 4313367040646743,1740318019946551931] |