| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 43 |
| 5 | 172 |
| 6 | 852 |
| 7 | 3719 |
| 8 | 19290 |
| 9 | 90469 |
| 10 | 481825 |
| 11 | 2295973 |
| 12 | 12812880 |
| 13 | 62122518 |
| 14 | 346770241 |
| 15 | 1744884177 |
| 16 | 9830723932 |
| 17 | 49268101457 |
| 18 | 285020577850 |
| 19 | 1438021808125 |
| 20 | 8300553742452 |
| 21 | 42955378420263 |
| 22 | 247456097485363 |
| 23 | 1271978597532857 |
| 24 | 7520668963944205 |
| 25 | 38700952324615078 |
[1,1,3,10,43,172,852,3719,19290,90469,481825, 2295973,12812880,62122518,346770241,1744884177, 9830723932,49268101457,285020577850,1438021808125, 8300553742452,42955378420263,247456097485363, 1271978597532857,7520668963944205, 38700952324615078] |