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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 65 |
| 3 | 536 |
| 4 | 4481 |
| 5 | 37928 |
| 6 | 324545 |
| 7 | 2803256 |
| 8 | 24405761 |
| 9 | 213887048 |
| 10 | 1884629825 |
| 11 | 16679193176 |
| 12 | 148135411841 |
| 13 | 1319377419368 |
| 14 | 11777507763905 |
| 15 | 105319346802296 |
| 16 | 943126559710721 |
| 17 | 8454906106826888 |
| 18 | 75861524447454785 |
| 19 | 681125306429182616 |
[1,8,65,536,4481,37928,324545,2803256,24405761, 213887048,1884629825,16679193176,148135411841, 1319377419368,11777507763905,105319346802296, 943126559710721,8454906106826888, 75861524447454785,681125306429182616] |