The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 5 |
| 8 | 8 |
| 9 | 13 |
| 10 | 24 |
| 11 | 45 |
| 12 | 85 |
| 13 | 160 |
| 14 | 297 |
| 15 | 550 |
| 16 | 1024 |
| 17 | 1920 |
| 18 | 3626 |
| 19 | 6885 |
| 20 | 13107 |
| 21 | 24989 |
| 22 | 47709 |
| 23 | 91225 |
| 24 | 174760 |
| 25 | 335462 |
| 26 | 645120 |
| 27 | 1242600 |
| 28 | 2396745 |
| 29 | 4628480 |
| 30 | 8948385 |
| 31 | 17318945 |
| 32 | 33554432 |
| 33 | 65074253 |
| 34 | 126320640 |
| 35 | 245424829 |
| 36 | 477218560 |
| 37 | 928645120 |
| 38 | 1808414181 |
| 39 | 3524082400 |
[0,0,0,1,2,3,5,8,13,24,45,85,160,297,550,1024, 1920,3626,6885,13107,24989,47709,91225,174760, 335462,645120,1242600,2396745,4628480,8948385, 17318945,33554432,65074253,126320640,245424829, 477218560,928645120,1808414181,3524082400] |