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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 8 |
| 4 | 64 |
| 5 | 512 |
| 6 | 4096 |
| 7 | 125000 |
| 8 | 1000000 |
| 9 | 8000000 |
| 10 | 40707584 |
| 11 | 325660672 |
| 12 | 2605285376 |
| 13 | 13858588808 |
| 14 | 110868710464 |
| 15 | 886949683712 |
| 16 | 4748408986112 |
| 17 | 37987271888896 |
| 18 | 303898175111168 |
| 19 | 1628455122125000 |
| 20 | 13027640977000000 |
[0,1,8,64,512,4096,125000,1000000,8000000, 40707584,325660672,2605285376,13858588808, 110868710464,886949683712,4748408986112, 37987271888896,303898175111168,1628455122125000, 13027640977000000] |