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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | -1 |
| 4 | 3 |
| 5 | -14 |
| 6 | 47 |
| 7 | -227 |
| 8 | 1343 |
| 9 | -7772 |
| 10 | 53145 |
| 11 | -408102 |
| 12 | 3284325 |
| 13 | -29130869 |
| 14 | 279951911 |
| 15 | -2849836062 |
| 16 | 31093638892 |
| 17 | -361102774004 |
| 18 | 4425942618296 |
| 19 | -57338046436904 |
| 20 | 782321680405477 |
| 21 | -11197403028728939 |
| 22 | 167963239073106477 |
[1,0,1,-1,3,-14,47,-227,1343,-7772,53145,-408102, 3284325,-29130869,279951911,-2849836062, 31093638892,-361102774004,4425942618296, -57338046436904,782321680405477, -11197403028728939,167963239073106477] |