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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 210 |
| 4 | 105840 |
| 5 | 838252800 |
| 6 | 129459762432000 |
| 7 | 466521199899955200000 |
| 8 | 45727437650097816797184000000 |
| 9 | 139352822480378029387123167068160000000 |
| 10 | 14863555768518278744824500982673408262144000000000 |
| 11 | 61707340455179609358720715109663452970925870494515200000000000 |
[1,5,210,105840,838252800,129459762432000, 466521199899955200000, 45727437650097816797184000000, 139352822480378029387123167068160000000, 14863555768518278744824500982673408262144000000000\ , 61707340455179609358720715109663452970925870494515\ 200000000000] |