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A066519
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Gaps between successive numbers with an anti-divisor class sum of zero.
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2
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1, 1, 3, 3, 6, 2, 4, 7, 2, 6, 7, 3, 1, 4, 3, 8, 7, 2, 1, 3, 5, 10, 2, 1, 3, 3, 2, 1, 5, 1, 1, 1, 4, 4, 2, 2, 2, 9, 2, 6, 9, 1, 1, 4, 4, 1, 3, 6, 1, 3, 22, 1, 9, 1, 1, 2, 2, 4, 7, 3, 5, 4, 1, 2, 20, 1, 2, 6, 1, 4, 4, 9, 5, 1, 4, 5, 2, 7, 8, 2, 2, 9, 2, 2, 1, 5, 3, 1, 4, 1, 12, 16, 13, 5, 1, 9, 2, 1, 3, 3
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OFFSET
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1,3
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COMMENTS
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See A066272 for definition of anti-divisor.
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LINKS
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EXAMPLE
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f(1)=f(2)=f(3)=0, f(4)=1, f(5)=-1, f(6)=0, so the first 3 gaps are 1, 1, 3.
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MATHEMATICA
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a[ n_ ] := Sum[ Which[ Mod[ n, d ]==(d-1)/2, -1, Mod[ n, d ]==(d+1)/2, 1, True, 0 ], {d, 2, n-1} ]; z=Select[ Range[ 1, 500 ], a[ # ]==0& ]; Drop[ z, 1 ]-Drop[ z, -1 ]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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