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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | 0 |
| 5 | -3 |
| 6 | 9 |
| 7 | -15 |
| 8 | 6 |
| 9 | 56 |
| 10 | -222 |
| 11 | 456 |
| 12 | -322 |
| 13 | -1562 |
| 14 | 7604 |
| 15 | -18062 |
| 16 | 18544 |
| 17 | 46676 |
| 18 | -293986 |
| 19 | 797456 |
| 20 | -1066316 |
| 21 | -1265854 |
| 22 | 11945620 |
| 23 | -36984046 |
| 24 | 60359006 |
| 25 | 20788743 |
| 26 | -493365441 |
| 27 | 1756737971 |
| 28 | -3368998030 |
| 29 | 835358767 |
| 30 | 20230816709 |
| 31 | -84341891481 |
| 32 | 185935403556 |
[1,-1,1,0,-3,9,-15,6,56,-222,456,-322,-1562,7604, -18062,18544,46676,-293986,797456,-1066316, -1265854,11945620,-36984046,60359006,20788743, -493365441,1756737971,-3368998030,835358767, 20230816709,-84341891481,185935403556] |