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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 118 |
| 3 | 1152 |
| 4 | 11772 |
| 5 | 128160 |
| 6 | 1494576 |
| 7 | 18679680 |
| 8 | 249815520 |
| 9 | 3566142720 |
| 10 | 54187574400 |
| 11 | 873962127360 |
| 12 | 14920424467200 |
| 13 | 268923168460800 |
| 14 | 5104647388108800 |
| 15 | 101811581061120000 |
| 16 | 2129097359866982400 |
| 17 | 46590736318156800000 |
| 18 | 1064901291126220800000 |
| 19 | 25379394670728806400000 |
[1,12,118,1152,11772,128160,1494576,18679680, 249815520,3566142720,54187574400,873962127360, 14920424467200,268923168460800,5104647388108800, 101811581061120000,2129097359866982400, 46590736318156800000,1064901291126220800000, 25379394670728806400000] |