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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | -3 |
| 5 | 12 |
| 6 | 117 |
| 7 | 336 |
| 8 | -903 |
| 9 | -2096 |
| 10 | 111529 |
| 11 | 1043328 |
| 12 | 687093 |
| 13 | -29488704 |
| 14 | 320199453 |
| 15 | 8894706432 |
| 16 | 44530596081 |
| 17 | -389860902656 |
| 18 | 254346923089 |
| 19 | 170568226222080 |
| 20 | 2006766293627373 |
| 21 | -6327905330549760 |
| 22 | -141849542553657147 |
[1,1,1,0,-3,12,117,336,-903,-2096,111529,1043328, 687093,-29488704,320199453,8894706432,44530596081, -389860902656,254346923089,170568226222080, 2006766293627373,-6327905330549760, -141849542553657147] |