The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 13 |
| 6 | 23 |
| 7 | 65 |
| 8 | 104 |
| 9 | 252 |
| 10 | 846 |
| 11 | 1237 |
| 12 | 3659 |
| 13 | 7244 |
| 14 | 10086 |
| 15 | 19195 |
| 16 | 48341 |
| 17 | 116599 |
| 18 | 155037 |
| 19 | 356168 |
| 20 | 609236 |
| 21 | 792905 |
| 22 | 1716485 |
| 23 | 2832213 |
| 24 | 5887815 |
| 25 | 15116625 |
| 26 | 23911833 |
| 27 | 29983570 |
| 28 | 46873052 |
| 29 | 58443395 |
| 30 | 90374471 |
| 31 | 394641602 |
| 32 | 593224103 |
| 33 | 1082063335 |
| 34 | 1318608063 |
| 35 | 3477935702 |
| 36 | 4207389268 |
| 37 | 7398721009 |
| 38 | 12885091292 |
| 39 | 18555597522 |
| 40 | 31831360281 |
| 41 | 54145147464 |
| 42 | 64517020844 |
[0,0,1,3,13,23,65,104,252,846,1237,3659,7244, 10086,19195,48341,116599,155037,356168,609236, 792905,1716485,2832213,5887815,15116625,23911833, 29983570,46873052,58443395,90374471,394641602, 593224103,1082063335,1318608063,3477935702, 4207389268,7398721009,12885091292,18555597522, 31831360281,54145147464,64517020844] |