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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | -1 |
| 5 | 9 |
| 6 | 9 |
| 7 | 1 |
| 8 | -1 |
| 9 | 18 |
| 10 | 9 |
| 11 | -5 |
| 12 | 5 |
| 13 | 15 |
| 14 | 90 |
| 15 | 27 |
| 16 | 35 |
| 17 | -35 |
| 18 | 225 |
| 19 | 405 |
| 20 | 81 |
| 21 | -105 |
| 22 | 105 |
| 23 | -35 |
| 24 | 630 |
| 25 | 567 |
| 26 | 81 |
| 27 | 1155 |
| 28 | -1155 |
| 29 | 490 |
| 30 | -105 |
| 31 | 4158 |
| 32 | 2268 |
| 33 | 243 |
| 34 | 15015 |
| 35 | -15015 |
| 36 | 6895 |
| 37 | 945 |
| 38 | -10206 |
| 39 | -23814 |
| 40 | -8748 |
| 41 | -729 |
| 42 | 75075 |
| 43 | -75075 |
| 44 | 35700 |
| 45 | -10675 |
| 46 | 2835 |
| 47 | -945 |
| 48 | 34020 |
| 49 | 41310 |
| 50 | 10935 |
| 51 | 729 |
[1,1,3,-1,9,9,1,-1,18,9,-5,5,15,90,27,35,-35,225, 405,81,-105,105,-35,630,567,81,1155,-1155,490, -105,4158,2268,243,15015,-15015,6895,945,-10206, -23814,-8748,-729,75075,-75075,35700,-10675,2835, -945,34020,41310,10935,729] |