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A160759
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Integer averages of n values of Pi(n^2) for some n, where Pi(n) is the number of primes <= n.
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0
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0, 1, 2, 3, 201, 235, 265, 431, 1705, 11744, 33946, 622755, 3446493, 8134880, 14287916, 208340425, 223689468
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OFFSET
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1,3
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COMMENTS
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For values of n: 1, 2, 3, 4, 62, 68, 73, 97, 213, 624, 1116, 5364, 13350, 21048, 28351, 116151, 120562, ..., . [From Robert G. Wilson v, Jun 05 2009]
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LINKS
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Table of n, a(n) for n=1..17.
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FORMULA
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1/k*Sum {j=1..k} PrimePi_(j^2) is an integer. [From Robert G. Wilson v, Jun 05 2009]
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MATHEMATICA
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lst = {}; s = 0; k = 1; While[k < 239600, s = s + PrimePi[k^2]; If[ Mod[s, k] == 0, AppendTo[lst, s/c]]; k++ ]; lst [From Robert G. Wilson v, Jun 05 2009]
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CROSSREFS
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Cf. A050248, Integer averages of n primes for some n.
Sequence in context: A042701 A106715 A106817 * A191835 A195264 A037274
Adjacent sequences: A160756 A160757 A160758 * A160760 A160761 A160762
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KEYWORD
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nonn
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AUTHOR
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Daniel Tisdale, May 25 2009
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EXTENSIONS
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More terms from Robert G. Wilson v, Jun 05 2009
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STATUS
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approved
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