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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | -3 |
| 5 | 10 |
| 6 | -100 |
| 7 | 525 |
| 8 | -4935 |
| 9 | 32940 |
| 10 | -339750 |
| 11 | 2618275 |
| 12 | -30387775 |
| 13 | 251013750 |
| 14 | -3301268100 |
| 15 | 26222434875 |
| 16 | -400587471375 |
| 17 | 2197651183000 |
| 18 | -45694778418250 |
| 19 | -233584427890125 |
| 20 | -1331937583104375 |
[1,0,0,0,-3,10,-100,525,-4935,32940,-339750, 2618275,-30387775,251013750,-3301268100, 26222434875,-400587471375,2197651183000, -45694778418250,-233584427890125, -1331937583104375] |