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| n | a(n) |
|---|---|
| 5 | 240 |
| 6 | 2880 |
| 7 | 33600 |
| 8 | 403200 |
| 9 | 5093760 |
| 10 | 68275200 |
| 11 | 972787200 |
| 12 | 14724864000 |
| 13 | 236396160000 |
| 14 | 4016659046400 |
| 15 | 72067387392000 |
| 16 | 1362306097152000 |
| 17 | 27071765360640000 |
| 18 | 564357385912320000 |
| 19 | 12317692759916544000 |
| 20 | 280955128203509760000 |
[240,2880,33600,403200,5093760,68275200,972787200, 14724864000,236396160000,4016659046400, 72067387392000,1362306097152000,27071765360640000, 564357385912320000,12317692759916544000, 280955128203509760000] |