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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 8 |
| 3 | 8 |
| 4 | 120 |
| 5 | 288 |
| 6 | 2360 |
| 7 | 8632 |
| 8 | 55224 |
| 9 | 249656 |
| 10 | 1443128 |
| 11 | 7243552 |
| 12 | 40366040 |
| 13 | 213357880 |
| 14 | 1178216264 |
| 15 | 6395922296 |
| 16 | 35375108728 |
| 17 | 194951335888 |
[1,0,8,8,120,288,2360,8632,55224,249656,1443128, 7243552,40366040,213357880,1178216264,6395922296, 35375108728,194951335888] |