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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | -2 |
| 6 | 1 |
| 7 | 6 |
| 8 | -13 |
| 9 | 8 |
| 10 | -1 |
| 11 | 720 |
| 12 | -1566 |
| 13 | 973 |
| 14 | -128 |
| 15 | 1 |
| 16 | 3628800 |
| 17 | -7893360 |
| 18 | 4905486 |
| 19 | -646093 |
| 20 | 5168 |
| 21 | -1 |
| 22 | 1316818944000 |
| 23 | -2864346105600 |
| 24 | 1780110653040 |
| 25 | -234459133326 |
| 26 | 1876009933 |
| 27 | -368048 |
| 28 | 1 |
| 29 | 52563198423859200000 |
| 30 | -114335531944833024000 |
| 31 | 71056323779613177600 |
| 32 | -9358860113257929840 |
[1,0,1,1,-2,1,6,-13,8,-1,720,-1566,973,-128,1, 3628800,-7893360,4905486,-646093,5168,-1, 1316818944000,-2864346105600,1780110653040, -234459133326,1876009933,-368048,1, 52563198423859200000,-114335531944833024000, 71056323779613177600,-9358860113257929840] |