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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 15 |
| 4 | 120 |
| 5 | 7140 |
| 6 | 25493370 |
| 7 | 324955944231765 |
| 8 | 52798182845779144865989623495 |
| 9 | 1393824055908163580110066696496417846029512708072933195765 |
| 10 | 971372749414141756744711053350258180262238679505115309556108472465628097348257583700704919225793663496284373565495 |
[3,6,15,120,7140,25493370,324955944231765, 52798182845779144865989623495, 13938240559081635801100666964964178460295127080729\ 33195765, 97137274941414175674471105335025818026223867950511\ 53095561084724656280973482575837007049192257936634\ 96284373565495] |