The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 3 |
| 8 | 6 |
| 9 | 12 |
| 10 | 20 |
| 11 | 33 |
| 12 | 59 |
| 13 | 104 |
| 14 | 181 |
| 15 | 319 |
| 16 | 557 |
| 17 | 971 |
| 18 | 1705 |
| 19 | 2985 |
| 20 | 5218 |
| 21 | 9138 |
| 22 | 15993 |
| 23 | 27984 |
| 24 | 48992 |
| 25 | 85749 |
| 26 | 150061 |
| 27 | 262656 |
| 28 | 459721 |
| 29 | 804597 |
| 30 | 1408263 |
| 31 | 2464815 |
| 32 | 4313962 |
| 33 | 7550509 |
| 34 | 13215258 |
| 35 | 23129801 |
| 36 | 40482775 |
| 37 | 70854694 |
| 38 | 124012664 |
[0,0,1,1,1,2,3,6,12,20,33,59,104,181,319,557,971, 1705,2985,5218,9138,15993,27984,48992,85749, 150061,262656,459721,804597,1408263,2464815, 4313962,7550509,13215258,23129801,40482775, 70854694,124012664] |