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| n | a(n) |
|---|---|
| 3 | 3 |
| 4 | 36 |
| 5 | 300 |
| 6 | 2520 |
| 7 | 22680 |
| 8 | 221760 |
| 9 | 2358720 |
| 10 | 27216000 |
| 11 | 339292800 |
| 12 | 4550515200 |
| 13 | 65383718400 |
| 14 | 1002550348800 |
| 15 | 16345929600000 |
| 16 | 282457663488000 |
| 17 | 5157467707392000 |
| 18 | 99236792438784000 |
| 19 | 2007144156745728000 |
| 20 | 42575785143091200000 |
| 21 | 945182430176624640000 |
| 22 | 21918014191663349760000 |
[3,36,300,2520,22680,221760,2358720,27216000, 339292800,4550515200,65383718400,1002550348800, 16345929600000,282457663488000,5157467707392000, 99236792438784000,2007144156745728000, 42575785143091200000,945182430176624640000, 21918014191663349760000] |