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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 255150 |
| 5 | 22208256 |
| 6 | 848836800 |
| 7 | 18527097600 |
| 8 | 267722771400 |
| 9 | 2823129792000 |
| 10 | 23221189252800 |
| 11 | 156216399897600 |
| 12 | 890233857251550 |
| 13 | 4413205102118400 |
| 14 | 19428198670785600 |
| 15 | 77215562567974656 |
| 16 | 280728337687134750 |
[1,0,0,0,255150,22208256,848836800,18527097600, 267722771400,2823129792000,23221189252800, 156216399897600,890233857251550,4413205102118400, 19428198670785600,77215562567974656, 280728337687134750] |