The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 2 | 144 |
| 3 | 576 |
| 4 | 1920 |
| 5 | 5760 |
| 6 | 16128 |
| 7 | 43008 |
| 8 | 110592 |
| 9 | 276480 |
| 10 | 675840 |
| 11 | 1622016 |
| 12 | 3833856 |
| 13 | 8945664 |
| 14 | 20643840 |
| 15 | 47185920 |
| 16 | 106954752 |
| 17 | 240648192 |
| 18 | 537919488 |
| 19 | 1195376640 |
| 20 | 2642411520 |
| 21 | 5813305344 |
| 22 | 12733906944 |
| 23 | 27783069696 |
| 24 | 60397977600 |
| 25 | 130862284800 |
| 26 | 282662535168 |
| 27 | 608811614208 |
[144,576,1920,5760,16128,43008,110592,276480, 675840,1622016,3833856,8945664,20643840,47185920, 106954752,240648192,537919488,1195376640, 2642411520,5813305344,12733906944,27783069696, 60397977600,130862284800,282662535168, 608811614208] |