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A063671
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Positions of nonzero coefficients in cyclotomic polynomial Phi_n(x), A063670 in binary.
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5
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10, 11, 11, 111, 101, 11111, 111, 1111111, 10001, 1001001, 11111, 11111111111, 10101, 1111111111111, 1111111, 110111011, 100000001, 11111111111111111, 1001001, 1111111111111111111, 101010101, 1101101011011, 11111111111
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OFFSET
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0,1
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COMMENTS
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a(0) could also be 1. - T. D. Noe, Oct 29 2007
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LINKS
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FORMULA
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a(n) = A063697(n) (the positive terms) + A063699(n) (the negative terms) (computed in any base, up to n=104).
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EXAMPLE
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Phi_15(x) = x^8 - x^7 + x^5 - x^4 + x^3 - x + 1, thus the 1-bits of a(15) are at positions 0,1,3,4,5,7 and 8, thus we get a(15) = 110111011.
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MAPLE
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MATHEMATICA
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a[n_] := FromDigits[Abs[CoefficientList[Cyclotomic[n, x], x]]]; a[0]=10; Table[a[n], {n, 0, 22}] (* Jean-François Alcover, Nov 02 2016 *)
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CROSSREFS
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KEYWORD
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nonn,base,nice
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AUTHOR
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STATUS
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approved
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