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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | 2 |
| 4 | 30 |
| 5 | 24 |
| 6 | 1 |
| 7 | 720 |
| 8 | 15 |
| 9 | 560 |
| 10 | 12 |
| 11 | 3628800 |
| 12 | 10 |
| 13 | 479001600 |
| 14 | 360 |
| 15 | 8 |
| 16 | 315 |
| 17 | 20922789888000 |
| 18 | 280 |
| 19 | 6402373705728000 |
| 20 | 6 |
| 21 | 240 |
| 22 | 1814400 |
| 23 | 1124000727777607680000 |
| 24 | 5 |
| 25 | 1596672 |
| 26 | 239500800 |
| 27 | 1478400 |
| 28 | 180 |
| 29 | 304888344611713860501504000000 |
| 30 | 4 |
| 31 | 265252859812191058636308480000000 |
[2,1,2,30,24,1,720,15,560,12,3628800,10,479001600, 360,8,315,20922789888000,280,6402373705728000,6, 240,1814400,1124000727777607680000,5,1596672, 239500800,1478400,180, 304888344611713860501504000000,4, 265252859812191058636308480000000] |