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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 20 |
| 6 | 48 |
| 7 | 112 |
| 8 | 864 |
| 9 | 2916 |
| 10 | 34560 |
| 11 | 152064 |
| 12 | 1728000 |
| 13 | 9360000 |
| 14 | 108864000 |
| 15 | 1049760000 |
| 16 | 10668672000 |
| 17 | 172802851200 |
| 18 | 2184944025600 |
| 19 | 32025036718080 |
| 20 | 438839318937600 |
| 21 | 6636767477760000 |
| 22 | 108637562880000000 |
| 23 | 1940004332259840000 |
| 24 | 24494663395141632000 |
| 25 | 673031429554176000000 |
[1,2,3,4,20,48,112,864,2916,34560,152064,1728000, 9360000,108864000,1049760000,10668672000, 172802851200,2184944025600,32025036718080, 438839318937600,6636767477760000, 108637562880000000,1940004332259840000, 24494663395141632000,673031429554176000000] |