The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 5 |
| 6 | 0 |
| 7 | 1 |
| 8 | 15 |
| 9 | 26 |
| 10 | 0 |
| 11 | 1 |
| 12 | 35 |
| 13 | 156 |
| 14 | 154 |
| 15 | 0 |
| 16 | 1 |
| 17 | 75 |
| 18 | 650 |
| 19 | 1540 |
| 20 | 1044 |
| 21 | 0 |
| 22 | 1 |
| 23 | 155 |
| 24 | 2340 |
| 25 | 10010 |
| 26 | 15660 |
| 27 | 8028 |
| 28 | 0 |
| 29 | 1 |
| 30 | 315 |
| 31 | 7826 |
| 32 | 53900 |
| 33 | 146160 |
| 34 | 168588 |
| 35 | 69264 |
| 36 | 0 |
| 37 | 1 |
| 38 | 635 |
| 39 | 25116 |
| 40 | 261954 |
| 41 | 1096200 |
| 42 | 2135448 |
| 43 | 1939392 |
| 44 | 663696 |
| 45 | 0 |
| 46 | 1 |
| 47 | 1275 |
| 48 | 78650 |
| 49 | 1196580 |
| 50 | 7256844 |
[0,0,1,0,1,5,0,1,15,26,0,1,35,156,154,0,1,75,650, 1540,1044,0,1,155,2340,10010,15660,8028,0,1,315, 7826,53900,146160,168588,69264,0,1,635,25116, 261954,1096200,2135448,1939392,663696,0,1,1275, 78650,1196580,7256844] |