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A161867
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Denominators of ratio of nonprimes in a square interval to that of nonprimes in that interval and its successor.
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4
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4, 8, 11, 5, 2, 7, 25, 29, 2, 35, 39, 21, 47, 2, 51, 28, 61, 64, 67, 35, 37, 79, 81, 83, 89, 93, 95, 33, 104, 2, 109, 113, 39, 121, 125, 65, 131, 133, 137, 47, 37, 151, 51, 2, 161, 165, 2, 171, 179, 89, 177, 184, 191, 49, 201, 199, 101, 207, 208, 43, 109, 55, 227, 2, 233, 119
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OFFSET
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1,1
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LINKS
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FORMULA
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The limit of this sequence of ratios is 1/2, as can be shown by setting an increasing lower bound on the ratio of composites in successive square intervals.
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EXAMPLE
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First few ratios are 1/4, 3/8, 5/11, 2/5, 1/2, 3/7, 12/25, 13/29.
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MATHEMATICA
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Denominator[Table[((2 n + 1) - (PrimePi[(n + 1)^2] - PrimePi[n^2]))/((4 n + 4) - (PrimePi[(n + 2)^2] - PrimePi[n^2])), {n, 1, 100}]] (* corrected by G. C. Greubel, Dec 20 2016)
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CROSSREFS
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Cf. A161865, numerators for this sequence.
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KEYWORD
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nonn,frac
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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