The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 32 |
| 4 | 138 |
| 5 | 612 |
| 6 | 2764 |
| 7 | 12700 |
| 8 | 58968 |
| 9 | 276528 |
| 10 | 1305745 |
| 11 | 6201839 |
| 12 | 29599678 |
| 13 | 141827398 |
| 14 | 681967982 |
| 15 | 3288696968 |
| 16 | 15900565194 |
| 17 | 77048864705 |
| 18 | 374090158891 |
| 19 | 1819483169075 |
| 20 | 8863255852580 |
| 21 | 43236468163514 |
| 22 | 211179733453264 |
| 23 | 1032648061022020 |
| 24 | 5054786347652530 |
| 25 | 24766533837228243 |
| 26 | 121452184499118348 |
[1,2,8,32,138,612,2764,12700,58968,276528,1305745, 6201839,29599678,141827398,681967982,3288696968, 15900565194,77048864705,374090158891, 1819483169075,8863255852580,43236468163514, 211179733453264,1032648061022020,5054786347652530, 24766533837228243,121452184499118348] |