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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 11160 |
| 5 | 0 |
| 6 | 1749888 |
| 7 | 22855680 |
| 8 | 232081500 |
| 9 | 1717223424 |
| 10 | 9366150528 |
| 11 | 38269550592 |
| 12 | 119637587496 |
| 13 | 286573658112 |
| 14 | 533982211840 |
| 15 | 771854598144 |
| 16 | 874731154374 |
| 17 | 771854598144 |
| 18 | 533982211840 |
| 19 | 286573658112 |
[1,0,0,0,11160,0,1749888,22855680,232081500, 1717223424,9366150528,38269550592,119637587496, 286573658112,533982211840,771854598144, 874731154374,771854598144,533982211840, 286573658112] |