The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 68 |
| 4 | 960 |
| 5 | 18832 |
| 6 | 471136 |
| 7 | 14324480 |
| 8 | 512733696 |
| 9 | 21119803136 |
| 10 | 984029612544 |
| 11 | 51169331031040 |
| 12 | 2937675286583296 |
| 13 | 184560174104465408 |
| 14 | 12594824112085327872 |
| 15 | 927757127285523243008 |
| 16 | 73369903633161123397632 |
| 17 | 6200198958236463387836416 |
[1,2,8,68,960,18832,471136,14324480,512733696, 21119803136,984029612544,51169331031040, 2937675286583296,184560174104465408, 12594824112085327872,927757127285523243008, 73369903633161123397632,6200198958236463387836416] |