The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 6 |
| 8 | 270 |
| 9 | 3195 |
| 10 | 21273 |
| 11 | 101484 |
| 12 | 386052 |
| 13 | 1243899 |
| 14 | 3527469 |
| 15 | 9035376 |
| 16 | 21297492 |
| 17 | 46838142 |
| 18 | 97131762 |
| 19 | 191517192 |
| 20 | 361427508 |
| 21 | 656353494 |
| 22 | 1152094086 |
| 23 | 1961910990 |
| 24 | 3251400894 |
| 25 | 5257953789 |
| 26 | 8315944731 |
| 27 | 12888836064 |
| 28 | 19609755396 |
[0,0,0,0,0,0,6,270,3195,21273,101484,386052, 1243899,3527469,9035376,21297492,46838142, 97131762,191517192,361427508,656353494,1152094086, 1961910990,3251400894,5257953789,8315944731, 12888836064,19609755396] |