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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 12 |
| 5 | 5 |
| 6 | 180 |
| 7 | 315 |
| 8 | 2240 |
| 9 | 567 |
| 10 | 907200 |
| 11 | 51975 |
| 12 | 13305600 |
| 13 | 289575 |
| 14 | 80720640 |
| 15 | 212837625 |
| 16 | 3487131648000 |
| 17 | 2297295 |
| 18 | 64023737057280 |
| 19 | 14849255421 |
| 20 | 28963119144960000 |
| 21 | 17717861581875 |
| 22 | 140500090972200960000 |
| 23 | 16436269594119375 |
| 24 | 6204484017332394393600 |
| 25 | 40639128117328125 |
[1,1,3,12,5,180,315,2240,567,907200,51975, 13305600,289575,80720640,212837625,3487131648000, 2297295,64023737057280,14849255421, 28963119144960000,17717861581875, 140500090972200960000,16436269594119375, 6204484017332394393600,40639128117328125] |