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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 16 |
| 3 | 1020 |
| 4 | 165536 |
| 5 | 49320160 |
| 6 | 23135212080 |
| 7 | 15630527512432 |
| 8 | 14347969660399360 |
| 9 | 17168404551237910944 |
| 10 | 25958066829841770846080 |
| 11 | 48399006022125586628932736 |
| 12 | 109114846124680246152236983296 |
| 13 | 292658282423729795503719053388032 |
| 14 | 921152122780387427929905530363699968 |
| 15 | 3362986922125901260144227986553038280960 |
[2,16,1020,165536,49320160,23135212080, 15630527512432,14347969660399360, 17168404551237910944,25958066829841770846080, 48399006022125586628932736, 109114846124680246152236983296, 292658282423729795503719053388032, 921152122780387427929905530363699968, 3362986922125901260144227986553038280960] |