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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | -3 |
| 2 | 12 |
| 3 | -36 |
| 4 | 105 |
| 5 | -303 |
| 6 | 873 |
| 7 | -2514 |
| 8 | 7239 |
| 9 | -20844 |
| 10 | 60018 |
| 11 | -172815 |
| 12 | 497601 |
| 13 | -1432785 |
| 14 | 4125540 |
| 15 | -11879019 |
| 16 | 34204272 |
| 17 | -98487276 |
| 18 | 283582809 |
| 19 | -816544155 |
| 20 | 2351145189 |
| 21 | -6769852758 |
| 22 | 19493014119 |
| 23 | -56127897168 |
| 24 | 161613838746 |
| 25 | -465348502119 |
| 26 | 1339917609189 |
| 27 | -3858138988821 |
[0,-3,12,-36,105,-303,873,-2514,7239,-20844,60018, -172815,497601,-1432785,4125540,-11879019, 34204272,-98487276,283582809,-816544155, 2351145189,-6769852758,19493014119,-56127897168, 161613838746,-465348502119,1339917609189, -3858138988821] |