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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 1 |
| 3 | 0 |
| 4 | -2 |
| 5 | 1 |
| 6 | 0 |
| 7 | -12 |
| 8 | 4 |
| 9 | 1 |
| 10 | 0 |
| 11 | -144 |
| 12 | 28 |
| 13 | 20 |
| 14 | 1 |
| 15 | 0 |
| 16 | -2880 |
| 17 | 216 |
| 18 | 508 |
| 19 | 50 |
| 20 | 1 |
| 21 | 0 |
| 22 | -86400 |
| 23 | -2592 |
| 24 | 17400 |
| 25 | 2548 |
| 26 | 98 |
| 27 | 1 |
| 28 | 0 |
| 29 | -3628800 |
| 30 | -449280 |
| 31 | 788688 |
| 32 | 153760 |
| 33 | 8568 |
| 34 | 168 |
| 35 | 1 |
| 36 | 0 |
| 37 | -203212800 |
| 38 | -42405120 |
| 39 | 46032768 |
| 40 | 11269008 |
| 41 | 811648 |
| 42 | 23016 |
| 43 | 264 |
| 44 | 1 |
| 45 | 0 |
| 46 | -14631321600 |
| 47 | -4187635200 |
| 48 | 3372731136 |
[1,-2,1,0,-2,1,0,-12,4,1,0,-144,28,20,1,0,-2880, 216,508,50,1,0,-86400,-2592,17400,2548,98,1,0, -3628800,-449280,788688,153760,8568,168,1,0, -203212800,-42405120,46032768,11269008,811648, 23016,264,1,0,-14631321600,-4187635200,3372731136] |