The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 40 |
| 3 | 200 |
| 4 | 841 |
| 5 | 3424 |
| 6 | 14136 |
| 7 | 56096 |
| 8 | 226248 |
| 9 | 902356 |
| 10 | 3613765 |
| 11 | 14445104 |
| 12 | 57743681 |
| 13 | 231001640 |
| 14 | 923890256 |
| 15 | 3695152852 |
[1,8,40,200,841,3424,14136,56096,226248,902356, 3613765,14445104,57743681,231001640,923890256, 3695152852] |