The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 56 |
| 6 | 241 |
| 7 | 1111 |
| 8 | 5748 |
| 9 | 31912 |
| 10 | 190328 |
| 11 | 1204317 |
| 12 | 8050341 |
| 13 | 56516303 |
| 14 | 415128256 |
| 15 | 3179020729 |
| 16 | 25308005049 |
| 17 | 208918893640 |
| 18 | 1784451646305 |
| 19 | 15739926014382 |
| 20 | 143130061546156 |
| 21 | 1339761466105929 |
| 22 | 12891329514544223 |
| 23 | 127351374611721837 |
| 24 | 1290198076415425548 |
| 25 | 13390893744153374776 |
[1,1,2,5,16,56,241,1111,5748,31912,190328,1204317, 8050341,56516303,415128256,3179020729,25308005049, 208918893640,1784451646305,15739926014382, 143130061546156,1339761466105929, 12891329514544223,127351374611721837, 1290198076415425548,13390893744153374776] |