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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 360 |
| 7 | 2520 |
| 8 | 10080 |
| 9 | 30240 |
| 10 | 151200 |
| 11 | 1663200 |
| 12 | 1663200 |
| 13 | 21621600 |
| 14 | 151351200 |
| 15 | 151351200 |
| 16 | 605404800 |
| 17 | 10291881600 |
| 18 | 30875644800 |
| 19 | 586637251200 |
| 20 | 586637251200 |
| 21 | 586637251200 |
| 22 | 6453009763200 |
| 23 | 148419224553600 |
| 24 | 148419224553600 |
| 25 | 742096122768000 |
| 26 | 9647249595984000 |
| 27 | 28941748787952000 |
[1,1,2,6,24,120,360,2520,10080,30240,151200, 1663200,1663200,21621600,151351200,151351200, 605404800,10291881600,30875644800,586637251200, 586637251200,586637251200,6453009763200, 148419224553600,148419224553600,742096122768000, 9647249595984000,28941748787952000] |