The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 8 |
| 3 | 112 |
| 4 | 2720 |
| 5 | 103552 |
| 6 | 5764352 |
| 7 | 445521664 |
| 8 | 45890802176 |
| 9 | 6094567045120 |
| 10 | 1015769696055296 |
| 11 | 207796011483160576 |
| 12 | 51221187819965530112 |
| 13 | 14979210670593626472448 |
| 14 | 5128843038563324804464640 |
| 15 | 2032875137444937697755332608 |
| 16 | 923598907664745712876929548288 |
[4,8,112,2720,103552,5764352,445521664, 45890802176,6094567045120,1015769696055296, 207796011483160576,51221187819965530112, 14979210670593626472448,5128843038563324804464640, 2032875137444937697755332608, 923598907664745712876929548288] |