| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 8 |
| 2 | 539 |
| 3 | 16632 |
| 4 | 364042 |
| 5 | 6510160 |
| 6 | 101817234 |
| 7 | 1447146512 |
| 8 | 19144522160 |
| 9 | 239513659776 |
| 10 | 2865559784050 |
| 11 | 33052451375152 |
| 12 | 369790434398988 |
| 13 | 4031805422883680 |
| 14 | 42996629236138928 |
| 15 | 449821323139340160 |
| 16 | 4627609615665499456 |
| 17 | 46907404618252667392 |
| 18 | 469254490696475078130 |
[0,8,539,16632,364042,6510160,101817234, 1447146512,19144522160,239513659776,2865559784050, 33052451375152,369790434398988,4031805422883680, 42996629236138928,449821323139340160, 4627609615665499456,46907404618252667392, 469254490696475078130] |