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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 56 |
| 4 | 43265712 |
| 5 | 219289731988435167257927904 |
| 6 | 8742218740996073061357349746759733054713953086811227917496519524423937904640 |
[2,3,56,43265712,219289731988435167257927904, 87422187409960730613573497467597330547139530868112\ 27917496519524423937904640] |