The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 9 |
| 3 | 32 |
| 4 | 104 |
| 5 | 360 |
| 6 | 1234 |
| 7 | 4224 |
| 8 | 14421 |
| 9 | 49292 |
| 10 | 168568 |
| 11 | 576373 |
| 12 | 1970380 |
| 13 | 6736149 |
| 14 | 23030217 |
| 15 | 78737741 |
| 16 | 269190899 |
| 17 | 920316854 |
| 18 | 3146418782 |
| 19 | 10757120910 |
| 20 | 36776888782 |
| 21 | 125734293267 |
| 22 | 429865563961 |
| 23 | 1469642274654 |
| 24 | 5024473730153 |
[4,9,32,104,360,1234,4224,14421,49292,168568, 576373,1970380,6736149,23030217,78737741, 269190899,920316854,3146418782,10757120910, 36776888782,125734293267,429865563961, 1469642274654,5024473730153] |