The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 40 |
| 4 | 169 |
| 5 | 723 |
| 6 | 3214 |
| 7 | 14570 |
| 8 | 66467 |
| 9 | 307797 |
| 10 | 1438868 |
| 11 | 6752762 |
| 12 | 31934236 |
| 13 | 151832097 |
| 14 | 723820039 |
| 15 | 3466177340 |
| 16 | 16655030010 |
| 17 | 80181728016 |
| 18 | 387141121436 |
| 19 | 1873550930655 |
| 20 | 9080050327816 |
| 21 | 44094481742754 |
| 22 | 214485799818078 |
| 23 | 1044473982743553 |
| 24 | 5093661578986069 |
| 25 | 24871301698286623 |
| 26 | 121549003554477777 |
[1,3,10,40,169,723,3214,14570,66467,307797, 1438868,6752762,31934236,151832097,723820039, 3466177340,16655030010,80181728016,387141121436, 1873550930655,9080050327816,44094481742754, 214485799818078,1044473982743553,5093661578986069, 24871301698286623,121549003554477777] |