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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | -2 |
| 4 | 0 |
| 5 | -6 |
| 6 | -2 |
| 7 | -10 |
| 8 | -6 |
| 9 | -20 |
| 10 | -20 |
| 11 | -22 |
| 12 | -64 |
| 13 | -22 |
| 14 | -144 |
| 15 | -74 |
| 16 | -188 |
| 17 | -212 |
| 18 | -326 |
| 19 | -642 |
| 20 | -332 |
| 21 | -1680 |
| 22 | -582 |
| 23 | -2904 |
| 24 | -1696 |
| 25 | -5798 |
| 26 | -4478 |
| 27 | -8942 |
| 28 | -13240 |
| 29 | -9018 |
| 30 | -34472 |
| 31 | -16158 |
| 32 | -54228 |
| 33 | -56482 |
| 34 | -99052 |
| 35 | -130104 |
| 36 | -121048 |
| 37 | -331382 |
| 38 | -177706 |
| 39 | -777622 |
| 40 | -422988 |
[1,0,0,-2,0,-6,-2,-10,-6,-20,-20,-22,-64,-22,-144, -74,-188,-212,-326,-642,-332,-1680,-582,-2904, -1696,-5798,-4478,-8942,-13240,-9018,-34472, -16158,-54228,-56482,-99052,-130104,-121048, -331382,-177706,-777622,-422988] |