The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 24 |
| 4 | 44 |
| 5 | 142 |
| 6 | 366 |
| 7 | 800 |
| 8 | 1636 |
| 9 | 4338 |
| 10 | 10154 |
| 11 | 18968 |
| 12 | 42368 |
| 13 | 80726 |
| 14 | 183914 |
| 15 | 401096 |
| 16 | 729944 |
| 17 | 1402098 |
| 18 | 2829814 |
| 19 | 5172416 |
| 20 | 10600836 |
| 21 | 21582558 |
| 22 | 37732782 |
| 23 | 70148512 |
| 24 | 127184636 |
| 25 | 236798322 |
| 26 | 416265730 |
| 27 | 804045376 |
| 28 | 1514022088 |
| 29 | 2581172630 |
[1,2,6,24,44,142,366,800,1636,4338,10154,18968, 42368,80726,183914,401096,729944,1402098,2829814, 5172416,10600836,21582558,37732782,70148512, 127184636,236798322,416265730,804045376, 1514022088,2581172630] |