The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 1 |
| 8 | 5 |
| 9 | 70 |
| 10 | 3547 |
| 11 | 868311 |
| 12 | 495369040 |
| 13 | 478905812650 |
[0,0,0,0,0,0,1,5,70,3547,868311,495369040, 478905812650] |