The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 16 |
| 5 | 16 |
| 6 | 192 |
| 7 | 192 |
| 8 | 6912 |
| 9 | 4608 |
| 10 | 230400 |
| 11 | 230400 |
| 12 | 11612160 |
| 13 | 11612160 |
| 14 | 1199923200 |
| 15 | 588349440 |
| 16 | 98594979840 |
| 17 | 98594979840 |
| 18 | 11076328488960 |
| 19 | 11076328488960 |
| 20 | 2102897147904000 |
| 21 | 1076597725593600 |
| 22 | 331238941183180800 |
| 23 | 331238941183180800 |
| 24 | 66325953940291584000 |
| 25 | 56326771107377971200 |
[1,2,2,16,16,192,192,6912,4608,230400,230400, 11612160,11612160,1199923200,588349440, 98594979840,98594979840,11076328488960, 11076328488960,2102897147904000,1076597725593600, 331238941183180800,331238941183180800, 66325953940291584000,56326771107377971200] |