| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 4 |
| 8 | 7 |
| 9 | 12 |
| 10 | 22 |
| 11 | 41 |
| 12 | 76 |
| 13 | 142 |
| 14 | 268 |
| 15 | 509 |
| 16 | 971 |
| 17 | 1861 |
| 18 | 3583 |
| 19 | 6925 |
| 20 | 13430 |
| 21 | 26128 |
| 22 | 50980 |
| 23 | 99735 |
| 24 | 195594 |
| 25 | 384454 |
| 26 | 757256 |
| 27 | 1494465 |
| 28 | 2954715 |
| 29 | 5851677 |
| 30 | 11607348 |
| 31 | 23058492 |
| 32 | 45870685 |
| 33 | 91371464 |
| 34 | 182231978 |
| 35 | 363871075 |
| 36 | 727364502 |
| 37 | 1455503056 |
| 38 | 2915461721 |
| 39 | 5845386764 |
| 40 | 11730347948 |
[1,0,0,1,1,1,2,4,7,12,22,41,76,142,268,509,971, 1861,3583,6925,13430,26128,50980,99735,195594, 384454,757256,1494465,2954715,5851677,11607348, 23058492,45870685,91371464,182231978,363871075, 727364502,1455503056,2915461721,5845386764, 11730347948] |