The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 9 |
| 7 | 18 |
| 8 | 37 |
| 9 | 73 |
| 10 | 145 |
| 11 | 287 |
| 12 | 570 |
| 13 | 1134 |
| 14 | 2264 |
| 15 | 4526 |
| 16 | 9061 |
| 17 | 18152 |
| 18 | 36374 |
| 19 | 72884 |
| 20 | 146011 |
| 21 | 292416 |
| 22 | 585422 |
| 23 | 1171632 |
| 24 | 2344136 |
| 25 | 4688821 |
| 26 | 9376832 |
| 27 | 18749169 |
| 28 | 37485358 |
| 29 | 74939850 |
| 30 | 149813328 |
| 31 | 299492966 |
| 32 | 598729533 |
| 33 | 1196987066 |
| 34 | 2393137399 |
| 35 | 4784846896 |
| 36 | 9567357951 |
[0,1,1,2,4,9,18,37,73,145,287,570,1134,2264,4526, 9061,18152,36374,72884,146011,292416,585422, 1171632,2344136,4688821,9376832,18749169,37485358, 74939850,149813328,299492966,598729533,1196987066, 2393137399,4784846896,9567357951] |