The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 52 |
| 4 | 552 |
| 5 | 10208 |
| 6 | 350112 |
| 7 | 23159760 |
| 8 | 3012389984 |
| 9 | 777296223040 |
| 10 | 399542726439936 |
| 11 | 409933997609848192 |
| 12 | 840366306053838941952 |
| 13 | 3443822768422065940362240 |
| 14 | 28218687132517064788995222528 |
| 15 | 462391421142204650963524251763968 |
| 16 | 15152566983759983965941543133445666304 |
[1,2,8,52,552,10208,350112,23159760,3012389984, 777296223040,399542726439936,409933997609848192, 840366306053838941952,3443822768422065940362240, 28218687132517064788995222528, 462391421142204650963524251763968, 15152566983759983965941543133445666304] |