The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 72 |
| 2 | 18360 |
| 3 | 5920200 |
| 4 | 2118223800 |
| 5 | 803927196072 |
| 6 | 316938365223480 |
| 7 | 128313095514575400 |
| 8 | 52976845635264939960 |
| 9 | 22204947580777261872000 |
| 10 | 9418997650746914743158360 |
| 11 | 4034374193416822645489549632 |
| 12 | 1741969558937890710303111545400 |
[1,72,18360,5920200,2118223800,803927196072, 316938365223480,128313095514575400, 52976845635264939960,22204947580777261872000, 9418997650746914743158360, 4034374193416822645489549632, 1741969558937890710303111545400] |