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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 60 |
| 6 | 5 |
| 7 | 80 |
| 8 | 720 |
| 9 | 7920 |
| 10 | 55440 |
| 11 | 55440 |
| 12 | 6160 |
| 13 | 6160 |
| 14 | 18480 |
| 15 | 425040 |
| 16 | 5525520 |
| 17 | 160240080 |
| 18 | 160240080 |
| 19 | 53413360 |
| 20 | 53413360 |
| 21 | 480720240 |
| 22 | 480720240 |
| 23 | 19709529840 |
| 24 | 19709529840 |
| 25 | 39419059680 |
| 26 | 197095298400 |
| 27 | 3350620072800 |
| 28 | 177582863858400 |
[1,2,4,12,60,5,80,720,7920,55440,55440,6160,6160, 18480,425040,5525520,160240080,160240080,53413360, 53413360,480720240,480720240,19709529840, 19709529840,39419059680,197095298400, 3350620072800,177582863858400] |