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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 60 |
| 7 | 1 |
| 8 | 5040 |
| 9 | 10080 |
| 10 | 15120 |
| 11 | 1 |
| 12 | 19958400 |
| 13 | 1 |
| 14 | 8648640 |
| 15 | 1816214400 |
| 16 | 1307674368000 |
| 17 | 1 |
| 18 | 88921857024000 |
| 19 | 1 |
| 20 | 5068545850368000 |
| 21 | 1689515283456000 |
| 22 | 14079294028800 |
| 23 | 1 |
| 24 | 12926008369442488320000 |
| 25 | 1077167364120207360000 |
[1,1,1,1,1,60,1,5040,10080,15120,1,19958400,1, 8648640,1816214400,1307674368000,1,88921857024000, 1,5068545850368000,1689515283456000, 14079294028800,1,12926008369442488320000, 1077167364120207360000] |