| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 16 |
| 3 | 60 |
| 4 | 177 |
| 5 | 869 |
| 6 | 3994 |
| 7 | 16348 |
| 8 | 71669 |
| 9 | 320252 |
| 10 | 1397642 |
| 11 | 6126487 |
| 12 | 27033698 |
| 13 | 118937813 |
| 14 | 522957359 |
| 15 | 2302293383 |
| 16 | 10134259558 |
| 17 | 44597178254 |
| 18 | 196288034748 |
| 19 | 863967834742 |
| 20 | 3802581182754 |
| 21 | 16736484491069 |
| 22 | 73664164496629 |
[1,16,60,177,869,3994,16348,71669,320252,1397642, 6126487,27033698,118937813,522957359,2302293383, 10134259558,44597178254,196288034748,863967834742, 3802581182754,16736484491069,73664164496629] |