The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 3 |
| 4 | 9 |
| 5 | 14 |
| 6 | 37 |
| 7 | 68 |
| 8 | 156 |
| 9 | 318 |
| 10 | 685 |
| 11 | 1362 |
| 12 | 2664 |
| 13 | 4645 |
| 14 | 7306 |
| 15 | 9594 |
| 16 | 10016 |
| 17 | 7605 |
| 18 | 4130 |
| 19 | 1539 |
| 20 | 444 |
| 21 | 86 |
| 22 | 16 |
| 23 | 1 |
| 24 | 1 |
[1,1,3,3,9,14,37,68,156,318,685,1362,2664,4645, 7306,9594,10016,7605,4130,1539,444,86,16,1,1] |