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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | -1 |
| 5 | 10 |
| 6 | -85 |
| 7 | 735 |
| 8 | -6699 |
| 9 | 64764 |
| 10 | -662780 |
| 11 | 7139000 |
| 12 | -80273116 |
| 13 | 931853208 |
| 14 | -10990479136 |
| 15 | 128253707400 |
| 16 | -1402525474414 |
| 17 | 12224484229744 |
| 18 | -9767136488568 |
| 19 | -3662083220408136 |
| 20 | 144120068237692294 |
| 21 | -4329792070579951500 |
| 22 | 118808185600297890950 |
[1,0,0,0,-1,10,-85,735,-6699,64764,-662780, 7139000,-80273116,931853208,-10990479136, 128253707400,-1402525474414,12224484229744, -9767136488568,-3662083220408136, 144120068237692294,-4329792070579951500, 118808185600297890950] |