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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 24 |
| 3 | 45 |
| 4 | 480 |
| 5 | 10080 |
| 6 | 24192 |
| 7 | 907200 |
| 8 | 1036800 |
| 9 | 239500800 |
| 10 | 106444800 |
| 11 | 9906624000 |
| 12 | 475517952000 |
| 13 | 15692092416000 |
| 14 | 4828336128000 |
| 15 | 8002967132160000 |
| 16 | 4268249137152000 |
| 17 | 51607012294656000 |
| 18 | 1202139815804928000 |
[6,24,45,480,10080,24192,907200,1036800,239500800, 106444800,9906624000,475517952000,15692092416000, 4828336128000,8002967132160000,4268249137152000, 51607012294656000,1202139815804928000] |