The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 0 |
| 6 | 2 |
| 7 | 6 |
| 8 | 15 |
| 9 | 44 |
| 10 | 74 |
| 11 | 202 |
| 12 | 351 |
| 13 | 766 |
| 14 | 1301 |
| 15 | 2626 |
| 16 | 4677 |
| 17 | 8993 |
| 18 | 16466 |
| 19 | 31671 |
| 20 | 60266 |
| 21 | 116751 |
| 22 | 229180 |
| 23 | 452667 |
| 24 | 905627 |
| 25 | 1815394 |
| 26 | 3673666 |
| 27 | 7429123 |
| 28 | 15109955 |
| 29 | 30696510 |
| 30 | 62512866 |
| 31 | 127140993 |
| 32 | 258745131 |
| 33 | 525845884 |
| 34 | 1068309682 |
| 35 | 2167462318 |
| 36 | 4393853912 |
| 37 | 8896007640 |
[1,0,2,0,2,6,15,44,74,202,351,766,1301,2626,4677, 8993,16466,31671,60266,116751,229180,452667, 905627,1815394,3673666,7429123,15109955,30696510, 62512866,127140993,258745131,525845884,1068309682, 2167462318,4393853912,8896007640] |