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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 135 |
| 4 | 3456 |
| 5 | 120245 |
| 6 | 5303040 |
| 7 | 283559227 |
| 8 | 17830210048 |
| 9 | 1289406976713 |
| 10 | 105435719470080 |
| 11 | 9619902621234191 |
| 12 | 968905466782150656 |
| 13 | 106779534666615500989 |
| 14 | 12781543241568143171584 |
| 15 | 1651368425166943566943875 |
| 16 | 229049483642619517308764160 |
| 17 | 33947359023461155854768564497 |
[1,1,8,135,3456,120245,5303040,283559227, 17830210048,1289406976713,105435719470080, 9619902621234191,968905466782150656, 106779534666615500989,12781543241568143171584, 1651368425166943566943875, 229049483642619517308764160, 33947359023461155854768564497] |