The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 16 |
| 6 | 34 |
| 7 | 82 |
| 8 | 252 |
| 9 | 890 |
| 10 | 3644 |
| 11 | 15390 |
| 12 | 67646 |
| 13 | 301210 |
| 14 | 1397898 |
| 15 | 6786792 |
| 16 | 35154332 |
[1,2,4,8,16,34,82,252,890,3644,15390,67646,301210, 1397898,6786792,35154332] |