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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 15 |
| 4 | 105 |
| 5 | 1155 |
| 6 | 1336335 |
| 7 | 892896284280 |
| 8 | 398631887241408183843480 |
| 9 | 19863422690705846097977473796903171171326157280 |
| 10 | 14091270035344566960604487534521565339065390839583445590118556137472614250693240040301050080 |
[1,2,6,15,105,1155,1336335,892896284280, 398631887241408183843480, 19863422690705846097977473796903171171326157280, 14091270035344566960604487534521565339065390839583\ 445590118556137472614250693240040301050080] |