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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 28 |
| 4 | 1171 |
| 5 | 337664 |
| 6 | 477339616 |
| 7 | 2872202032640 |
| 8 | 72057595967392816 |
| 9 | 7462505059899322983424 |
| 10 | 3169126500571074529242309120 |
| 11 | 5492677668532710795071526353530880 |
| 12 | 38716571525226776289479030777920527620096 |
| 13 | 1106936151351216411420552029913564178922327982080 |
[2,6,28,1171,337664,477339616,2872202032640, 72057595967392816,7462505059899322983424, 3169126500571074529242309120, 5492677668532710795071526353530880, 38716571525226776289479030777920527620096, 1106936151351216411420552029913564178922327982080] |