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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | 5 |
| 4 | -18 |
| 5 | 70 |
| 6 | -282 |
| 7 | 1179 |
| 8 | -5104 |
| 9 | 22634 |
| 10 | -102128 |
| 11 | 467637 |
| 12 | -2168208 |
| 13 | 10157664 |
| 14 | -48005858 |
| 15 | 228607728 |
| 16 | -1095885048 |
| 17 | 5284044080 |
| 18 | -25609804110 |
| 19 | 124693451466 |
| 20 | -609641464746 |
| 21 | 2991742731876 |
| 22 | -14731354000792 |
| 23 | 72761153346680 |
| 24 | -360397156557696 |
| 25 | 1789733084330806 |
| 26 | -8909067981051118 |
[1,-2,5,-18,70,-282,1179,-5104,22634,-102128, 467637,-2168208,10157664,-48005858,228607728, -1095885048,5284044080,-25609804110,124693451466, -609641464746,2991742731876,-14731354000792, 72761153346680,-360397156557696,1789733084330806, -8909067981051118] |