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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 194 |
| 3 | 9078 |
| 4 | 596760 |
| 5 | 50508120 |
| 6 | 5228520912 |
| 7 | 639915545808 |
| 8 | 90390815432064 |
| 9 | 14472947716917120 |
| 10 | 2590274418097708800 |
| 11 | 512433683486806447872 |
| 12 | 111036605823697437490176 |
| 13 | 26153418409614396515976192 |
| 14 | 6653213794092052464421939200 |
| 15 | 1817951594633556391548903168000 |
[1,7,194,9078,596760,50508120,5228520912, 639915545808,90390815432064,14472947716917120, 2590274418097708800,512433683486806447872, 111036605823697437490176, 26153418409614396515976192, 6653213794092052464421939200, 1817951594633556391548903168000] |