The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 3 |
| 6 | 9 |
| 7 | 9 |
| 8 | 12 |
| 9 | 23 |
| 10 | 54 |
| 11 | 77 |
| 12 | 116 |
| 13 | 205 |
| 14 | 352 |
| 15 | 697 |
| 16 | 1174 |
| 17 | 2013 |
| 18 | 3538 |
| 19 | 6209 |
| 20 | 10830 |
[1,1,1,3,3,3,9,9,12,23,54,77,116,205,352,697,1174, 2013,3538,6209,10830] |