The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 39 |
| 5 | 115 |
| 6 | 330 |
| 7 | 958 |
| 8 | 2708 |
| 9 | 7700 |
| 10 | 21474 |
| 11 | 59732 |
| 12 | 164126 |
| 13 | 447995 |
| 14 | 1211720 |
| 15 | 3258896 |
| 16 | 8699731 |
| 17 | 23100190 |
| 18 | 60985784 |
| 19 | 160172634 |
| 20 | 418505039 |
| 21 | 1088396720 |
| 22 | 2817751182 |
| 23 | 7262961898 |
| 24 | 18647741599 |
| 25 | 47690238685 |
| 26 | 121529569106 |
| 27 | 308617383361 |
| 28 | 781131731981 |
| 29 | 1970766138399 |
| 30 | 4957228945138 |
[1,2,5,14,39,115,330,958,2708,7700,21474,59732, 164126,447995,1211720,3258896,8699731,23100190, 60985784,160172634,418505039,1088396720, 2817751182,7262961898,18647741599,47690238685, 121529569106,308617383361,781131731981, 1970766138399,4957228945138] |