The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 2 |
| 4 | 2 |
| 5 | 2 |
| 6 | 5 |
| 7 | 14 |
| 8 | 44 |
| 9 | 127 |
| 10 | 325 |
| 11 | 779 |
| 12 | 1794 |
| 13 | 3988 |
| 14 | 8830 |
| 15 | 19835 |
| 16 | 45596 |
| 17 | 108019 |
| 18 | 262831 |
| 19 | 649761 |
| 20 | 1616713 |
| 21 | 4017231 |
| 22 | 9918784 |
| 23 | 24298996 |
| 24 | 59106476 |
| 25 | 143053467 |
| 26 | 345488183 |
| 27 | 834978807 |
| 28 | 2023884377 |
| 29 | 4926308772 |
| 30 | 12044390597 |
| 31 | 29559301172 |
| 32 | 72735281709 |
[2,2,2,2,2,5,14,44,127,325,779,1794,3988,8830, 19835,45596,108019,262831,649761,1616713,4017231, 9918784,24298996,59106476,143053467,345488183, 834978807,2023884377,4926308772,12044390597, 29559301172,72735281709] |