The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 3 | 2 |
| 4 | 9 |
| 5 | 39 |
| 6 | 134 |
| 7 | 394 |
| 8 | 1040 |
| 9 | 2542 |
| 10 | 5876 |
| 11 | 13039 |
| 12 | 28080 |
| 13 | 59163 |
| 14 | 122694 |
| 15 | 251576 |
| 16 | 511720 |
| 17 | 1035068 |
| 18 | 2085640 |
| 19 | 4191629 |
| 20 | 8409592 |
| 21 | 16852833 |
| 22 | 33748170 |
| 23 | 67549470 |
| 24 | 135164720 |
| 25 | 270410170 |
| 26 | 540918620 |
| 27 | 1081955995 |
| 28 | 2164054496 |
[2,9,39,134,394,1040,2542,5876,13039,28080,59163, 122694,251576,511720,1035068,2085640,4191629, 8409592,16852833,33748170,67549470,135164720, 270410170,540918620,1081955995,2164054496] |