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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 204 |
| 3 | 103320 |
| 4 | 182819520 |
| 5 | 886613565600 |
| 6 | 9973411835945040 |
| 7 | 230723130088707984000 |
| 8 | 10026790739932043582668800 |
| 9 | 762878670971305314645055065600 |
| 10 | 96049580303627434572710125880376000 |
| 11 | 19110279123993980912852049573590159155200 |
[0,2,204,103320,182819520,886613565600, 9973411835945040,230723130088707984000, 10026790739932043582668800, 762878670971305314645055065600, 96049580303627434572710125880376000, 19110279123993980912852049573590159155200] |