| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 56 |
| 3 | 67280 |
| 4 | 90728008 |
| 5 | 773360088 |
| 6 | 88877688800 |
| 7 | 57750008008000 |
| 8 | 77774704000080080000 |
| 9 | 77777677600000800800000 |
| 10 | 77777790720000008008000000 |
| 11 | 77773773000000080080000000 |
| 12 | 88888888788088888888088088888888 |
| 13 | 77777757750000000008008000000000 |
[0,56,67280,90728008,773360088,88877688800, 57750008008000,77774704000080080000, 77777677600000800800000, 77777790720000008008000000, 77773773000000080080000000, 88888888788088888888088088888888, 77777757750000000008008000000000] |