The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 14 |
| 3 | 56 |
| 4 | 168 |
| 5 | 448 |
| 6 | 1120 |
| 7 | 2688 |
| 8 | 6272 |
| 9 | 14336 |
| 10 | 32256 |
| 11 | 71680 |
| 12 | 157696 |
| 13 | 344064 |
| 14 | 745472 |
| 15 | 1605632 |
| 16 | 3440640 |
| 17 | 7340032 |
| 18 | 15597568 |
| 19 | 33030144 |
| 20 | 69730304 |
| 21 | 146800640 |
| 22 | 308281344 |
| 23 | 645922816 |
| 24 | 1350565888 |
| 25 | 2818572288 |
| 26 | 5872025600 |
| 27 | 12213813248 |
| 28 | 25367150592 |
[1,14,56,168,448,1120,2688,6272,14336,32256,71680, 157696,344064,745472,1605632,3440640,7340032, 15597568,33030144,69730304,146800640,308281344, 645922816,1350565888,2818572288,5872025600, 12213813248,25367150592] |