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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 12 |
| 3 | 396 |
| 4 | 25344 |
| 5 | 2661120 |
| 6 | 415134720 |
| 7 | 90084234240 |
| 8 | 25944259461120 |
| 9 | 9573431741153280 |
| 10 | 4403778600930508800 |
| 11 | 2470519795122015436800 |
| 12 | 1660189302321994373529600 |
| 13 | 1316530116741341538208972800 |
| 14 | 1216473827868999581305090867200 |
| 15 | 1295544626680484554089921773568000 |
[1,1,12,396,25344,2661120,415134720,90084234240, 25944259461120,9573431741153280, 4403778600930508800,2470519795122015436800, 1660189302321994373529600, 1316530116741341538208972800, 1216473827868999581305090867200, 1295544626680484554089921773568000] |