The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 7 |
| 8 | 28 |
| 9 | 84 |
| 10 | 210 |
| 11 | 462 |
| 12 | 924 |
| 13 | 1717 |
| 14 | 3017 |
| 15 | 5110 |
| 16 | 8568 |
| 17 | 14756 |
| 18 | 27132 |
| 19 | 54264 |
| 20 | 116281 |
| 21 | 257775 |
| 22 | 572264 |
| 23 | 1246784 |
| 24 | 2641366 |
| 25 | 5430530 |
| 26 | 10861060 |
| 27 | 21242341 |
| 28 | 40927033 |
| 29 | 78354346 |
| 30 | 150402700 |
| 31 | 291693136 |
| 32 | 574274008 |
| 33 | 1148548016 |
| 34 | 2326683921 |
| 35 | 4749439975 |
[0,0,0,0,0,0,1,7,28,84,210,462,924,1717,3017,5110, 8568,14756,27132,54264,116281,257775,572264, 1246784,2641366,5430530,10861060,21242341, 40927033,78354346,150402700,291693136,574274008, 1148548016,2326683921,4749439975] |