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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 33 |
| 3 | 1332 |
| 4 | 66660 |
| 5 | 3999960 |
| 6 | 279999720 |
| 7 | 22399997760 |
| 8 | 2015999979840 |
| 9 | 201599999798400 |
| 10 | 927359999990726400 |
| 11 | 1064447999999893555200 |
| 12 | 2058376319999997941623680 |
| 13 | 4439635199999999955603648000 |
| 14 | 10585935359999999998941406464000 |
| 15 | 27655756127999999999972344243872000 |
[1,33,1332,66660,3999960,279999720,22399997760, 2015999979840,201599999798400,927359999990726400, 1064447999999893555200,2058376319999997941623680, 4439635199999999955603648000, 10585935359999999998941406464000, 27655756127999999999972344243872000] |