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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 3 |
| 6 | 196 |
| 7 | 3784 |
| 8 | 49824 |
| 9 | 577247 |
| 10 | 6250795 |
| 11 | 64725830 |
| 12 | 651790197 |
| 13 | 6443528078 |
| 14 | 62906425823 |
| 15 | 608875308314 |
| 16 | 5858471079330 |
| 17 | 56139508762734 |
| 18 | 536478118777779 |
[0,0,0,0,3,196,3784,49824,577247,6250795,64725830, 651790197,6443528078,62906425823,608875308314, 5858471079330,56139508762734,536478118777779] |