The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 140 |
| 3 | 168000 |
| 4 | 812011200 |
| 5 | 11021058048000 |
| 6 | 339782903171712000 |
| 7 | 20692894514095964160000 |
| 8 | 2254632317437500000000000000 |
| 9 | 408212019690599470111653888000000 |
| 10 | 115985264066835726820369478446080000000 |
| 11 | 49409573278650211500346024173376634880000000 |
| 12 | 30404587048380414443886075636144408738201600000000 |
[1,1,140,168000,812011200,11021058048000, 339782903171712000,20692894514095964160000, 2254632317437500000000000000, 408212019690599470111653888000000, 115985264066835726820369478446080000000, 49409573278650211500346024173376634880000000, 30404587048380414443886075636144408738201600000000\ ] |