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A194881
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A number of sum-free sets related to fractional parts of multiples of a rational number in the range 1/3 to 2/3.
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1
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2, 3, 6, 8, 12, 15, 21, 25, 34, 38, 48, 54, 66, 72, 84, 92, 108, 117, 135, 143, 161, 171, 193, 205, 225, 237, 264, 276, 304, 316, 346, 362, 392, 408, 432, 450, 486, 504, 540, 556, 596, 614, 656, 676, 712, 734, 780, 804, 846
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OFFSET
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1,1
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COMMENTS
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Deserves a better title which mentions n in the sense that this is a sum-free set from a difference set with {1,....,n}.
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LINKS
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FORMULA
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a(n) = 1+sum_{j=1..n} A000010(3*j)/2.
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MAPLE
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A194881 := proc(n) 1+add(numtheory[phi](3*q), q=1..n)/2 ; end proc:
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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