The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 37 |
| 6 | 168 |
| 7 | 926 |
| 8 | 6181 |
| 9 | 47651 |
| 10 | 418546 |
| 11 | 4106264 |
| 12 | 44537519 |
| 13 | 528408261 |
| 14 | 6807428748 |
| 15 | 94588717554 |
| 16 | 1409927483625 |
| 17 | 22437711255279 |
| 18 | 379674820846534 |
| 19 | 6806486383431340 |
| 20 | 128862216628864163 |
| 21 | 2569080120361323721 |
| 22 | 53797824318887051264 |
| 23 | 1180533584545138213222 |
[1,1,2,4,11,37,168,926,6181,47651,418546,4106264, 44537519,528408261,6807428748,94588717554, 1409927483625,22437711255279,379674820846534, 6806486383431340,128862216628864163, 2569080120361323721,53797824318887051264, 1180533584545138213222] |