The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 12 |
| 4 | 620 |
| 5 | 87304 |
| 6 | 26312976 |
| 7 | 14616808192 |
| 8 | 13525751027392 |
| 9 | 19385778269260800 |
| 10 | 40739017561997799680 |
| 11 | 120278021410937387514880 |
| 12 | 482113680618029292368686080 |
| 13 | 2551154673732472157928033617920 |
| 14 | 17410560213476464590484763013222400 |
[1,1,12,620,87304,26312976,14616808192, 13525751027392,19385778269260800, 40739017561997799680,120278021410937387514880, 482113680618029292368686080, 2551154673732472157928033617920, 17410560213476464590484763013222400] |