The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 14 |
| 4 | 160 |
| 5 | 2202 |
| 6 | 28384 |
| 7 | 419302 |
| 8 | 8238080 |
| 9 | 193340978 |
| 10 | 4860711424 |
| 11 | 132391420350 |
| 12 | 4045976651776 |
| 13 | 137295166640842 |
| 14 | 5028417873133568 |
| 15 | 197042617602645398 |
| 16 | 8292209178735935488 |
| 17 | 374117497443421923426 |
| 18 | 17958577129581151387648 |
| 19 | 912189896002576287703918 |
[1,2,4,14,160,2202,28384,419302,8238080,193340978, 4860711424,132391420350,4045976651776, 137295166640842,5028417873133568, 197042617602645398,8292209178735935488, 374117497443421923426,17958577129581151387648, 912189896002576287703918] |