The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 6 |
| 3 | 210 |
| 4 | 330 |
| 5 | 46410 |
| 6 | 1009470 |
| 7 | 2454270 |
| 8 | 358888530 |
| 9 | 8804809860 |
| 10 | 14908423530 |
| 11 | 87770875982790 |
| 12 | 8644083578130 |
| 13 | 6461153376929140890 |
| 14 | 55507010099631090 |
| 15 | 435066914019898690530 |
| 16 | 12624989405621802949740 |
| 17 | 1768322825403098494530 |
[1,4,6,210,330,46410,1009470,2454270,358888530, 8804809860,14908423530,87770875982790, 8644083578130,6461153376929140890, 55507010099631090,435066914019898690530, 12624989405621802949740,1768322825403098494530] |