The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 8 |
| 3 | 440 |
| 4 | 13002 |
| 5 | 291782 |
| 6 | 5718464 |
| 7 | 103948054 |
| 8 | 1806753034 |
| 9 | 30539121806 |
| 10 | 507006229578 |
| 11 | 8318320069722 |
| 12 | 135401306105052 |
| 13 | 2192221953687972 |
| 14 | 35363748022460400 |
| 15 | 569037825802441810 |
| 16 | 9140526218802015968 |
| 17 | 146649357444276412850 |
| 18 | 2350864549078452042124 |
[0,8,440,13002,291782,5718464,103948054, 1806753034,30539121806,507006229578,8318320069722, 135401306105052,2192221953687972, 35363748022460400,569037825802441810, 9140526218802015968,146649357444276412850, 2350864549078452042124] |