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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | -1 |
| 4 | 1 |
| 5 | -3 |
| 6 | 1 |
| 7 | -1 |
| 8 | 15 |
| 9 | 15 |
| 10 | -1 |
| 11 | 1 |
| 12 | -35 |
| 13 | 145 |
| 14 | -35 |
| 15 | 1 |
| 16 | -1 |
| 17 | 63 |
| 18 | -1505 |
| 19 | -1505 |
| 20 | 63 |
| 21 | -1 |
| 22 | 1 |
| 23 | -99 |
| 24 | 5985 |
| 25 | -30387 |
| 26 | 5985 |
| 27 | -99 |
| 28 | 1 |
| 29 | -1 |
| 30 | 143 |
| 31 | -16401 |
| 32 | 539679 |
| 33 | 539679 |
| 34 | -16401 |
| 35 | 143 |
| 36 | -1 |
| 37 | 1 |
| 38 | -195 |
| 39 | 36465 |
| 40 | -3275811 |
| 41 | 18679617 |
| 42 | -3275811 |
| 43 | 36465 |
| 44 | -195 |
| 45 | 1 |
| 46 | -1 |
| 47 | 255 |
| 48 | -70785 |
| 49 | 12723711 |
| 50 | -506849409 |
| 51 | -506849409 |
| 52 | 12723711 |
| 53 | -70785 |
| 54 | 255 |
| 55 | -1 |
[1,-1,-1,1,-3,1,-1,15,15,-1,1,-35,145,-35,1,-1,63, -1505,-1505,63,-1,1,-99,5985,-30387,5985,-99,1,-1, 143,-16401,539679,539679,-16401,143,-1,1,-195, 36465,-3275811,18679617,-3275811,36465,-195,1,-1, 255,-70785,12723711,-506849409,-506849409, 12723711,-70785,255,-1] |