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A142345
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Primes of the form (p(n)+r(n))/3, where p(n)=n-th prime and r(n)=n-th nonprime.
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1
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3, 23, 29, 37, 41, 47, 61, 67, 83, 103, 113, 149, 157, 167, 193, 269, 277, 281, 331, 347, 439, 521, 569, 593, 677, 733, 823, 827, 877, 911, 1019, 1061, 1097, 1117, 1153, 1217, 1259, 1289, 1381, 1433, 1447, 1489, 1499, 1553, 1607, 1637, 1693, 1699, 1733, 1801
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OFFSET
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1,1
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LINKS
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Harvey P. Dale, Table of n, a(n) for n = 1..1000
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EXAMPLE
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If n=3, then (p(3)+r(3))/3=(5+4)/3=3=a(1).
If n=15, then (p(15)+r(15))/3=(47+22)/3=23=a(2).
If n=18, then (p(18)+r(18))/3=(61+26)/3=29=a(3).
If n=22, then (p(22)+r(22))/3=(79+32)/3=37=a(4).
If n=24, then (p(24)+r(24))/3=(89+34)/3=41=a(5), etc.
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MATHEMATICA
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Module[{nn=5000, pr, comp, len}, pr=Prime[Range[PrimePi[nn]]]; comp = Complement[ Range[0, nn], pr]; len = Min[ Length[pr], Length[comp]]; Select[Total[#]/3&/@Thread[ {Take[pr, len], Take[comp, len]}], PrimeQ]] (* Harvey P. Dale, Dec 04 2012 *)
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CROSSREFS
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Cf. A000040, A141468.
Sequence in context: A103361 A136090 A032688 * A217329 A133023 A098946
Adjacent sequences: A142342 A142343 A142344 * A142346 A142347 A142348
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KEYWORD
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nonn
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AUTHOR
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Juri-Stepan Gerasimov, Sep 19 2008
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EXTENSIONS
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167 inserted, 347 inserted and extended by R. J. Mathar, Nov 03 2008
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STATUS
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approved
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