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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 48 |
| 4 | 64512 |
| 5 | 20808990720 |
| 6 | 6658450862270054400 |
| 7 | 8590449816558320728896700416000 |
| 8 | 180165778137909187135292776823951671626301440000 |
| 9 | 246665746050863452218796304775365273357060390005370386894553088000000 |
[1,2,48,64512,20808990720,6658450862270054400, 8590449816558320728896700416000, 180165778137909187135292776823951671626301440000, 24666574605086345221879630477536527335706039000537\ 0386894553088000000] |