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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 24 |
| 5 | 15 |
| 6 | 720 |
| 7 | 315 |
| 8 | 8064 |
| 9 | 2835 |
| 10 | 3628800 |
| 11 | 155925 |
| 12 | 95800320 |
| 13 | 6081075 |
| 14 | 87178291200 |
| 15 | 638512875 |
| 16 | 4184557977600 |
| 17 | 10854718875 |
| 18 | 6402373705728000 |
| 19 | 1856156927625 |
| 20 | 97316080327065600 |
| 21 | 194896477400625 |
| 22 | 1124000727777607680000 |
| 23 | 2900518163668125 |
| 24 | 9545360026665222144000 |
[1,1,2,3,24,15,720,315,8064,2835,3628800,155925, 95800320,6081075,87178291200,638512875, 4184557977600,10854718875,6402373705728000, 1856156927625,97316080327065600,194896477400625, 1124000727777607680000,2900518163668125, 9545360026665222144000] |