The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 9 |
| 5 | 16 |
| 6 | 41 |
| 7 | 426 |
| 8 | 467 |
| 9 | 4162 |
| 10 | 33763 |
| 11 | 37925 |
| 12 | 413013 |
| 13 | 863951 |
| 14 | 1276964 |
| 15 | 2140915 |
| 16 | 7699709 |
| 17 | 9840624 |
| 18 | 17540333 |
| 19 | 781615276 |
| 20 | 799155609 |
| 21 | 1580770885 |
| 22 | 5541468264 |
| 23 | 7122239149 |
| 24 | 12663707413 |
| 25 | 32449653975 |
| 26 | 337160247163 |
| 27 | 369609901138 |
| 28 | 3294039456267 |
| 29 | 26721925551274 |
[1,1,2,7,9,16,41,426,467,4162,33763,37925,413013, 863951,1276964,2140915,7699709,9840624,17540333, 781615276,799155609,1580770885,5541468264, 7122239149,12663707413,32449653975,337160247163, 369609901138,3294039456267,26721925551274] |