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A153636
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Primes of the form 4x^3 + 27y^2, with x>0.
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3
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31, 59, 283, 499, 743, 1327, 1399, 1579, 1823, 2687, 3271, 3299, 3371, 3559, 3767, 4027, 4243, 4567, 4639, 5323, 5351, 6079, 8059, 8123, 8563, 9463, 9851, 9887, 10111, 10247, 11003, 11119, 11399, 11939, 12163, 13127, 13163, 14243, 14783, 15907
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OFFSET
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1,1
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LINKS
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T. D. Noe, Table of n, a(n) for n = 1..1000
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MATHEMATICA
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nn=10^5; Select[Sort[Flatten[Table[4a^3+27b^2, {b, Sqrt[nn/27]}, {a, ((nn-27b^2)/4)^(1/3)}]]], PrimeQ[ # ] &]
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PROG
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(PARI) is(p)=for(b=1, sqrtint(max(0, p-4)\27), my(t=p-27*b^2); if(t%4==0&&ispower(t/4, 3), return(isprime(p)))); 0 \\ Charles R Greathouse IV, Jun 06 2013
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CROSSREFS
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A153635 (positive or negative x).
Cf. A154291.
Sequence in context: A043953 A327447 A139954 * A109840 A108293 A316349
Adjacent sequences: A153633 A153634 A153635 * A153637 A153638 A153639
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KEYWORD
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nonn
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AUTHOR
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T. D. Noe, Dec 29 2008
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STATUS
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approved
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