The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 139 |
| 4 | 5473 |
| 5 | 357721 |
| 6 | 34988647 |
| 7 | 4784061619 |
| 8 | 871335013633 |
| 9 | 203906055033841 |
| 10 | 59618325600871687 |
| 11 | 21297483077038703899 |
| 12 | 9127322584507530151393 |
| 13 | 4621897483978366951337161 |
| 14 | 2730069675607609356178641127 |
| 15 | 1860452328661957054823447670979 |
| 16 | 1448802510679254790311316267306753 |
[1,1,7,139,5473,357721,34988647,4784061619, 871335013633,203906055033841,59618325600871687, 21297483077038703899,9127322584507530151393, 4621897483978366951337161, 2730069675607609356178641127, 1860452328661957054823447670979, 1448802510679254790311316267306753] |