The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | -20 |
| 3 | 920 |
| 4 | -95600 |
| 5 | 17588000 |
| 6 | -5034785600 |
| 7 | 2068322672000 |
| 8 | -1153339941728000 |
| 9 | 838147215114560000 |
| 10 | -769492266756037760000 |
| 11 | 870869784123573927680000 |
| 12 | -1191080747725445120960000000 |
| 13 | 1936606018449416970940544000000 |
| 14 | -3692030834904045806243452160000000 |
| 15 | 8156631422332715861303860160000000000 |
| 16 | -20671774666617006397027638099614720000000 |
[1,2,-20,920,-95600,17588000,-5034785600, 2068322672000,-1153339941728000, 838147215114560000,-769492266756037760000, 870869784123573927680000, -1191080747725445120960000000, 1936606018449416970940544000000, -3692030834904045806243452160000000, 8156631422332715861303860160000000000, -20671774666617006397027638099614720000000] |