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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 12 |
| 7 | 12 |
| 8 | 48 |
| 9 | 144 |
| 10 | 1440 |
| 11 | 1440 |
| 12 | 17280 |
| 13 | 17280 |
| 14 | 241920 |
| 15 | 18144000 |
| 16 | 145152000 |
| 17 | 145152000 |
| 18 | 2612736000 |
| 19 | 2612736000 |
| 20 | 10450944000 |
| 21 | 219469824000 |
| 22 | 4828336128000 |
| 23 | 4828336128000 |
| 24 | 115880067072000 |
| 25 | 579400335360000 |
| 26 | 15064408719360000 |
| 27 | 135579678474240000 |
| 28 | 26573616980951040000 |
| 29 | 26573616980951040000 |
[1,1,1,2,2,12,12,48,144,1440,1440,17280,17280, 241920,18144000,145152000,145152000,2612736000, 2612736000,10450944000,219469824000,4828336128000, 4828336128000,115880067072000,579400335360000, 15064408719360000,135579678474240000, 26573616980951040000,26573616980951040000] |