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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 30 |
| 4 | 351137972965951 |
| 5 | 8596208716179446431 |
| 6 | 698211042943963834650959743951 |
| 7 | 744014385572130806167897354113929551 |
| 8 | 901203402294977554329263775346819632824908852456695769189267773301 |
[2,6,30,351137972965951,8596208716179446431, 698211042943963834650959743951, 744014385572130806167897354113929551, 90120340229497755432926377534681963282490885245669\ 5769189267773301] |