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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | -1 |
| 3 | 15 |
| 4 | -5 |
| 5 | 1 |
| 6 | 35 |
| 7 | -35 |
| 8 | 7 |
| 9 | -1 |
| 10 | 315 |
| 11 | -105 |
| 12 | 63 |
| 13 | -3 |
| 14 | 1 |
| 15 | 693 |
| 16 | -1155 |
| 17 | 231 |
| 18 | -33 |
| 19 | 11 |
| 20 | -1 |
| 21 | 3003 |
| 22 | -3003 |
| 23 | 3003 |
| 24 | -143 |
| 25 | 143 |
| 26 | -13 |
| 27 | 1 |
| 28 | 6435 |
| 29 | -15015 |
| 30 | 9009 |
| 31 | -2145 |
| 32 | 715 |
| 33 | -13 |
| 34 | 1 |
| 35 | -1 |
| 36 | 109395 |
| 37 | -36465 |
| 38 | 51051 |
| 39 | -7293 |
| 40 | 12155 |
| 41 | -221 |
| 42 | 17 |
| 43 | -17 |
| 44 | 1 |
| 45 | 230945 |
| 46 | -692835 |
| 47 | 138567 |
| 48 | -46189 |
| 49 | 46189 |
| 50 | -4199 |
| 51 | 323 |
| 52 | -323 |
| 53 | 19 |
| 54 | -1 |
[1,3,-1,15,-5,1,35,-35,7,-1,315,-105,63,-3,1,693, -1155,231,-33,11,-1,3003,-3003,3003,-143,143,-13, 1,6435,-15015,9009,-2145,715,-13,1,-1,109395, -36465,51051,-7293,12155,-221,17,-17,1,230945, -692835,138567,-46189,46189,-4199,323,-323,19,-1] |