| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 45 |
| 5 | 226 |
| 6 | 1113 |
| 7 | 5230 |
| 8 | 23565 |
| 9 | 102826 |
| 10 | 438273 |
| 11 | 1836550 |
| 12 | 7601685 |
| 13 | 31183426 |
| 14 | 127084233 |
| 15 | 515429470 |
| 16 | 2083077405 |
| 17 | 8396552026 |
| 18 | 33779262993 |
| 19 | 135696871990 |
| 20 | 544528258725 |
| 21 | 2183337968626 |
| 22 | 8749031918553 |
| 23 | 35043178292110 |
| 24 | 140313885993645 |
| 25 | 561679104393226 |
[0,1,3,10,45,226,1113,5230,23565,102826,438273, 1836550,7601685,31183426,127084233,515429470, 2083077405,8396552026,33779262993,135696871990, 544528258725,2183337968626,8749031918553, 35043178292110,140313885993645,561679104393226] |