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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 36 |
| 3 | 1920 |
| 4 | 210000 |
| 5 | 39191040 |
| 6 | 11181360960 |
| 7 | 4534378168320 |
| 8 | 2481970620729600 |
| 9 | 1764322560000000000 |
| 10 | 1580868516481859404800 |
| 11 | 1743505552795995891302400 |
| 12 | 2321376488366363008816435200 |
| 13 | 3671767205084150828189614080000 |
[1,2,36,1920,210000,39191040,11181360960, 4534378168320,2481970620729600, 1764322560000000000,1580868516481859404800, 1743505552795995891302400, 2321376488366363008816435200, 3671767205084150828189614080000] |