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A234256
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Cubes t^3 = (p+q+r)/3 which are the arithmetic mean of three consecutive primes such that p < t^3 < q < r.
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2
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5735339, 10503459, 73560059, 253636137, 393832837, 761048497, 791453125, 1064332261, 1829276567, 2014698447, 2487813875, 2893640625, 4533086375, 7845011803, 14437662875, 45998156287, 55611739513, 62429032063, 63378025803, 72877493233, 87115050737, 104154702625
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OFFSET
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1,1
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LINKS
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EXAMPLE
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5735339 is in the sequence because 5735339 = 179^3 = (5735291+5735357+5735369)/3, the arithmetic mean of three consecutive primes.
10503459 is in the sequence because 10503459 = 219^3 = (10503443+10503461+10503473)/3, the arithmetic mean of three consecutive primes.
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MAPLE
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with(numtheory):KD := proc() local a, b, d, e, f; a:=n^3; b:=prevprime(a); d:=nextprime(a); e:=nextprime(d); f:=(b+d+e)/3; if a=f then RETURN (a); fi; end: seq(KD(), n=2..10000);
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PROG
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(PARI) list(lim)=my(v=List(), p=2, q=3, t); forprime(r=5, nextprime(nextprime(lim\3+1)+1), t=(p+q+r)/3; if(denominator(t)==1 && ispower(t, 3) && t < q, listput(v, t)); p=q; q=r); Vec(v) \\ Charles R Greathouse IV, Jan 03 2014
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CROSSREFS
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Cf. A062703 (squares: sum of two consecutive primes).
Cf. A069495 (squares: arithmetic mean of two consecutive primes).
Cf. A234240 (cubes: arithmetic mean of two consecutive primes).
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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