The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 17 |
| 3 | 105 |
| 4 | 672 |
| 5 | 4490 |
| 6 | 31466 |
| 7 | 231445 |
| 8 | 1784788 |
| 9 | 14404218 |
| 10 | 121421075 |
| 11 | 1066906979 |
| 12 | 9753108510 |
| 13 | 92586250999 |
| 14 | 911156724048 |
[3,17,105,672,4490,31466,231445,1784788,14404218, 121421075,1066906979,9753108510,92586250999, 911156724048] |