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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 16 |
| 6 | 48 |
| 7 | 288 |
| 8 | 576 |
| 9 | 1728 |
| 10 | 8640 |
| 11 | 86400 |
| 12 | 259200 |
| 13 | 3110400 |
| 14 | 21772800 |
| 15 | 108864000 |
| 16 | 217728000 |
| 17 | 3483648000 |
| 18 | 10450944000 |
| 19 | 188116992000 |
| 20 | 940584960000 |
| 21 | 6584094720000 |
| 22 | 72425041920000 |
| 23 | 1593350922240000 |
| 24 | 4780052766720000 |
| 25 | 23900263833600000 |
| 26 | 310703429836800000 |
[1,1,2,4,16,48,288,576,1728,8640,86400,259200, 3110400,21772800,108864000,217728000,3483648000, 10450944000,188116992000,940584960000, 6584094720000,72425041920000,1593350922240000, 4780052766720000,23900263833600000, 310703429836800000] |