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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | -2 |
| 7 | 2 |
| 8 | -2 |
| 9 | 4 |
| 10 | -1 |
| 11 | 4 |
| 12 | -7 |
| 13 | 10 |
| 14 | -19 |
| 15 | 20 |
| 16 | -20 |
| 17 | 34 |
| 18 | -42 |
| 19 | 64 |
| 20 | -100 |
| 21 | 126 |
| 22 | -178 |
| 23 | 258 |
| 24 | -326 |
| 25 | 464 |
| 26 | -675 |
| 27 | 936 |
| 28 | -1371 |
| 29 | 1888 |
| 30 | -2550 |
| 31 | 3690 |
| 32 | -5208 |
| 33 | 7292 |
| 34 | -10467 |
| 35 | 14742 |
| 36 | -20808 |
| 37 | 29610 |
| 38 | -41586 |
| 39 | 59052 |
| 40 | -84438 |
| 41 | 119602 |
| 42 | -170153 |
| 43 | 242256 |
| 44 | -343534 |
| 45 | 489550 |
| 46 | -697815 |
[2,2,1,2,2,-2,2,-2,4,-1,4,-7,10,-19,20,-20,34,-42, 64,-100,126,-178,258,-326,464,-675,936,-1371,1888, -2550,3690,-5208,7292,-10467,14742,-20808,29610, -41586,59052,-84438,119602,-170153,242256,-343534, 489550,-697815] |