The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 48 |
| 6 | 173 |
| 7 | 714 |
| 8 | 3114 |
| 9 | 14936 |
| 10 | 80434 |
| 11 | 447839 |
| 12 | 2724103 |
| 13 | 17442771 |
| 14 | 114379899 |
| 15 | 784149081 |
| 16 | 5708691485 |
| 17 | 43849291330 |
| 18 | 342473913399 |
| 19 | 2803269796341 |
| 20 | 23620771158594 |
| 21 | 201815957246321 |
| 22 | 1793779464521955 |
| 23 | 16342108667160301 |
| 24 | 154171144824008979 |
[1,1,2,5,14,48,173,714,3114,14936,80434,447839, 2724103,17442771,114379899,784149081,5708691485, 43849291330,342473913399,2803269796341, 23620771158594,201815957246321,1793779464521955, 16342108667160301,154171144824008979] |