The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 53 |
| 3 | 333 |
| 4 | 1805 |
| 5 | 8953 |
| 6 | 41389 |
| 7 | 180718 |
| 8 | 757748 |
| 9 | 3072208 |
| 10 | 12100344 |
| 11 | 46606802 |
| 12 | 176082080 |
| 13 | 653863108 |
| 14 | 2394225532 |
| 15 | 8658131447 |
| 16 | 30954618019 |
| 17 | 109609761829 |
| 18 | 384756220575 |
| 19 | 1339683464511 |
| 20 | 4632090161405 |
| 21 | 15913128409903 |
| 22 | 54338332894979 |
[7,53,333,1805,8953,41389,180718,757748,3072208, 12100344,46606802,176082080,653863108,2394225532, 8658131447,30954618019,109609761829,384756220575, 1339683464511,4632090161405,15913128409903, 54338332894979] |