The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 1 |
| 7 | 0 |
| 8 | 1 |
| 9 | 0 |
| 10 | 2 |
| 11 | 0 |
| 12 | 2 |
| 13 | 0 |
| 14 | 4 |
| 15 | 0 |
| 16 | 6 |
| 17 | 0 |
| 18 | 11 |
| 19 | 0 |
| 20 | 18 |
| 21 | 0 |
| 22 | 37 |
| 23 | 0 |
| 24 | 66 |
| 25 | 0 |
| 26 | 135 |
| 27 | 0 |
| 28 | 265 |
| 29 | 0 |
| 30 | 552 |
| 31 | 0 |
| 32 | 1132 |
| 33 | 0 |
| 34 | 2410 |
| 35 | 0 |
| 36 | 5098 |
| 37 | 0 |
| 38 | 11020 |
| 39 | 0 |
| 40 | 23846 |
| 41 | 0 |
[1,1,0,1,0,1,0,1,0,2,0,2,0,4,0,6,0,11,0,18,0,37,0, 66,0,135,0,265,0,552,0,1132,0,2410,0,5098,0,11020, 0,23846,0] |