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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 16 |
| 3 | 280 |
| 4 | 8900 |
| 5 | 552752 |
| 6 | 68635317 |
| 7 | 17747766886 |
| 8 | 9421503162646 |
| 9 | 10606582683139102 |
| 10 | 24593238398265693575 |
| 11 | 121227430181311808878846 |
| 12 | 1234571538047080619811567488 |
| 13 | 26705899629138438568650919545084 |
[2,16,280,8900,552752,68635317,17747766886, 9421503162646,10606582683139102, 24593238398265693575,121227430181311808878846, 1234571538047080619811567488, 26705899629138438568650919545084] |