The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 9 |
| 3 | 135 |
| 4 | 2890 |
| 5 | 71639 |
| 6 | 1967545 |
| 7 | 58125959 |
| 8 | 1813561210 |
| 9 | 59034994415 |
| 10 | 1987910416810 |
| 11 | 68818255912790 |
| 12 | 2437897047570874 |
| 13 | 88061136002276310 |
| 14 | 3234416650430634090 |
| 15 | 120525771933269446806 |
| 16 | 4548292982313797644875 |
[1,0,9,135,2890,71639,1967545,58125959,1813561210, 59034994415,1987910416810,68818255912790, 2437897047570874,88061136002276310, 3234416650430634090,120525771933269446806, 4548292982313797644875] |