The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 57 |
| 5 | 197 |
| 6 | 727 |
| 7 | 2749 |
| 8 | 10427 |
| 9 | 40413 |
| 10 | 160104 |
| 11 | 635452 |
| 12 | 2540981 |
| 13 | 10308191 |
| 14 | 41986778 |
| 15 | 171455171 |
| 16 | 706159913 |
| 17 | 2922368795 |
| 18 | 12112409612 |
| 19 | 50441850877 |
| 20 | 210971954246 |
| 21 | 883890089373 |
| 22 | 3713026773797 |
| 23 | 15649807553384 |
| 24 | 66089155172539 |
| 25 | 279569747937615 |
| 26 | 1185459574168434 |
| 27 | 5036367375807659 |
[1,2,5,17,57,197,727,2749,10427,40413,160104, 635452,2540981,10308191,41986778,171455171, 706159913,2922368795,12112409612,50441850877, 210971954246,883890089373,3713026773797, 15649807553384,66089155172539,279569747937615, 1185459574168434,5036367375807659] |