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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | 1 |
| 4 | 1 |
| 5 | -1 |
| 6 | 1 |
| 7 | 2 |
| 8 | -3 |
| 9 | -1 |
| 10 | -11 |
| 11 | 17 |
| 12 | 46 |
| 13 | 217 |
| 14 | -143 |
| 15 | 2383 |
| 16 | 10797 |
| 17 | 19054 |
| 18 | 497689 |
| 19 | 2407303 |
| 20 | -18692747 |
| 21 | -184111831 |
| 22 | -1592624618 |
| 23 | 26447728169 |
| 24 | 396185367129 |
| 25 | -372098609569 |
| 26 | 104735294255689 |
| 27 | 1574163501502418 |
| 28 | -29166210748027547 |
| 29 | 1549967994300724111 |
[1,-2,1,1,-1,1,2,-3,-1,-11,17,46,217,-143,2383, 10797,19054,497689,2407303,-18692747,-184111831, -1592624618,26447728169,396185367129, -372098609569,104735294255689,1574163501502418, -29166210748027547,1549967994300724111] |