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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | 3 |
| 5 | -10 |
| 6 | 35 |
| 7 | -119 |
| 8 | 360 |
| 9 | -792 |
| 10 | -33 |
| 11 | 12779 |
| 12 | -82525 |
| 13 | 305861 |
| 14 | -552011 |
| 15 | -126321 |
| 16 | -8385020 |
| 17 | 138177591 |
| 18 | -433073834 |
| 19 | -5366414982 |
| 20 | 51203452090 |
| 21 | 123835509276 |
| 22 | -4174647911014 |
| 23 | 5274854624423 |
| 24 | 373574363131841 |
| 25 | -2054088594386738 |
| 26 | -34047892948849106 |
| 27 | 391005463740951942 |
[1,1,-1,3,-10,35,-119,360,-792,-33,12779,-82525, 305861,-552011,-126321,-8385020,138177591, -433073834,-5366414982,51203452090,123835509276, -4174647911014,5274854624423,373574363131841, -2054088594386738,-34047892948849106, 391005463740951942] |