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A124478
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a(n) = prime(n) - floor((2/n)*Sum_{i=1..n} prime(i)).
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1
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-2, -2, -1, -1, 0, 0, 1, 0, 1, 4, 2, 5, 5, 3, 4, 6, 8, 6, 8, 8, 6, 8, 7, 9, 13, 12, 10, 10, 7, 7, 17, 16, 17, 14, 19, 17, 18, 19, 18, 19, 20, 17, 22, 19, 18, 16, 23, 29, 28, 25, 24, 25, 21, 26, 27, 28, 28, 25, 26, 25, 22, 27, 35, 34, 30, 29, 37, 38, 42, 38, 37, 37, 40, 40, 40, 39, 39, 41, 40, 42
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OFFSET
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1,1
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COMMENTS
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Robert Mandl conjectured and Rosser and Schoenfeld proved that prime(n)/2 > (Sum_{i=1..n} prime(i))/n for n >= 9 (implying that a(n) > 0 for n >= 9).
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LINKS
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MATHEMATICA
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Table[Prime[n] - Floor[(2/n)*Sum[Prime[i], {i, n}]], {n, 100}] (* Michael De Vlieger, Jan 31 2015 *)
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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