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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | -56 |
| 3 | 840 |
| 4 | -14712 |
| 5 | 279944 |
| 6 | -5613496 |
| 7 | 116703944 |
| 8 | -2491139832 |
| 9 | 54255679240 |
| 10 | -1200518812472 |
| 11 | 26905864347208 |
| 12 | -609402981845112 |
| 13 | 13925251619910792 |
| 14 | -320604043308655288 |
| 15 | 7429310292469872072 |
| 16 | -173131499233512939000 |
| 17 | 4054648130127668125192 |
| 18 | -95374579073091515463224 |
| 19 | 2252203702571454839335240 |
[1,7,-56,840,-14712,279944,-5613496,116703944, -2491139832,54255679240,-1200518812472, 26905864347208,-609402981845112,13925251619910792, -320604043308655288,7429310292469872072, -173131499233512939000,4054648130127668125192, -95374579073091515463224, 2252203702571454839335240] |