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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 28 |
| 4 | 12600 |
| 5 | 69699849 |
| 6 | 4070693024640 |
| 7 | 2484046163254367574 |
| 8 | 15778915364062895746351104 |
| 9 | 1040828457711477326843036225608036 |
| 10 | 711789875509887224494712166194197254144000 |
| 11 | 5040627715175514814159607456023227379139001458908168 |
[1,1,28,12600,69699849,4070693024640, 2484046163254367574,15778915364062895746351104, 1040828457711477326843036225608036, 711789875509887224494712166194197254144000, 50406277151755148141596074560232273791390014589081\ 68] |