| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 16 |
| 3 | 512 |
| 4 | 34816 |
| 5 | 3821312 |
| 6 | 618121216 |
| 7 | 138682959872 |
| 8 | 41171702972416 |
| 9 | 15610723195092992 |
| 10 | 7357121913006063616 |
| 11 | 4217775794187229724672 |
| 12 | 2889975739296119171055616 |
| 13 | 2332177121915783600628826112 |
[0,2,16,512,34816,3821312,618121216,138682959872, 41171702972416,15610723195092992, 7357121913006063616,4217775794187229724672, 2889975739296119171055616, 2332177121915783600628826112] |