The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 19 |
| 5 | 46 |
| 6 | 161 |
| 7 | 799 |
| 8 | 4021 |
| 9 | 17932 |
| 10 | 71311 |
| 11 | 268639 |
| 12 | 1045731 |
| 13 | 4464576 |
| 14 | 20500010 |
| 15 | 95221503 |
| 16 | 429913365 |
| 17 | 1879365529 |
| 18 | 8112744634 |
| 19 | 35452835755 |
| 20 | 158833086233 |
| 21 | 725458442577 |
| 22 | 3329609464605 |
| 23 | 15194309369384 |
| 24 | 68837584452055 |
| 25 | 311257278509193 |
| 26 | 1413730859134250 |
| 27 | 6469321177004978 |
[1,3,8,19,46,161,799,4021,17932,71311,268639, 1045731,4464576,20500010,95221503,429913365, 1879365529,8112744634,35452835755,158833086233, 725458442577,3329609464605,15194309369384, 68837584452055,311257278509193,1413730859134250, 6469321177004978] |