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A091291
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Numbers x such that the quotient q=(sigma[x]+sigma[x+1])/sigma[2x+1] is smaller than 0.5, that is (sigma[x]+sigma[x+1])/>2.sigma[2x+1]; sigma=A000203.
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1
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1283782, 3445942, 4662157, 5743237, 7770262, 8806297, 8986477, 9572062, 9920137, 10472962, 11356537, 11554042, 12635122, 12870742
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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f[x_] := (DivisorSigma[1, x]+DivisorSigma[1, x+1])/DivisorSigma[1, 2*x+1] Do[s=f[n]; If[ !Greater[s, 0.5], Print[{n, s//N}]]
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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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