The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 51 |
| 4 | 541 |
| 5 | 6756 |
| 6 | 96205 |
| 7 | 1530025 |
| 8 | 26775550 |
| 9 | 509861195 |
| 10 | 10472109149 |
| 11 | 230368347780 |
| 12 | 5396308081285 |
| 13 | 133949699318945 |
| 14 | 3508794554854054 |
| 15 | 96648143868171171 |
| 16 | 2790590111082279405 |
| 17 | 84231759174460743700 |
| 18 | 2651416546964399982909 |
| 19 | 86848041397350751409257 |
[1,1,6,51,541,6756,96205,1530025,26775550, 509861195,10472109149,230368347780,5396308081285, 133949699318945,3508794554854054, 96648143868171171,2790590111082279405, 84231759174460743700,2651416546964399982909, 86848041397350751409257] |