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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | -2 |
| 4 | 4 |
| 5 | -7 |
| 6 | 10 |
| 7 | -10 |
| 8 | 1 |
| 9 | 26 |
| 10 | -80 |
| 11 | 161 |
| 12 | -242 |
| 13 | 242 |
| 14 | 1 |
| 15 | -730 |
| 16 | 2188 |
| 17 | -4376 |
| 18 | 6580 |
| 19 | -6733 |
| 20 | 1140 |
| 21 | 13718 |
| 22 | -32945 |
| 23 | 18920 |
| 24 | 158356 |
| 25 | -851599 |
| 26 | 2896920 |
| 27 | -8097220 |
| 28 | 20058301 |
| 29 | -45540944 |
| 30 | 96506230 |
| 31 | -193012459 |
| 32 | 367077448 |
| 33 | -667617643 |
| 34 | 1166803110 |
| 35 | -1968991970 |
| 36 | 3225375253 |
[2,1,-2,4,-7,10,-10,1,26,-80,161,-242,242,1,-730, 2188,-4376,6580,-6733,1140,13718,-32945,18920, 158356,-851599,2896920,-8097220,20058301, -45540944,96506230,-193012459,367077448, -667617643,1166803110,-1968991970,3225375253] |