The OEIS is supported by the many generous donors to the OEIS Foundation.
A081507 as a simple table
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 8 |
| 6 | 108 |
| 7 | 144 |
| 8 | 334 |
| 9 | 1422 |
| 10 | 4824 |
| 11 | 16502 |
| 12 | 19050 |
| 13 | 23262 |
[0,2,4,6,8,108,144,334,1422,4824,16502,19050, 23262] |