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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -5 |
| 3 | 25 |
| 4 | -125 |
| 5 | 620 |
| 6 | -3055 |
| 7 | 14935 |
| 8 | -72320 |
| 9 | 346120 |
| 10 | -1632435 |
| 11 | 7555615 |
| 12 | -34103940 |
| 13 | 148616480 |
| 14 | -614229500 |
| 15 | 2321723005 |
| 16 | -7293541865 |
| 17 | 11847720800 |
| 18 | 80050256480 |
| 19 | -1182000043580 |
| 20 | 10263664188460 |
| 21 | -75379977023875 |
| 22 | 508865668922995 |
| 23 | -3262422374486260 |
| 24 | 20187692749822600 |
| 25 | -121673379897635840 |
[1,-5,25,-125,620,-3055,14935,-72320,346120, -1632435,7555615,-34103940,148616480,-614229500, 2321723005,-7293541865,11847720800,80050256480, -1182000043580,10263664188460,-75379977023875, 508865668922995,-3262422374486260, 20187692749822600,-121673379897635840] |