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A107161
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Primes of the form 2x^2 + 27y^2.
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2
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2, 29, 59, 227, 251, 269, 293, 419, 443, 677, 683, 773, 821, 827, 1013, 1187, 1277, 1301, 1373, 1451, 1493, 1523, 1709, 1733, 1811, 1901, 1949, 2027, 2237, 2243, 2339, 2357, 2381, 2477, 2579, 2693, 2699, 2909, 3299, 3371, 3389, 3413, 3467
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OFFSET
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1,1
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COMMENTS
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Discriminant = -216. See A107132 for more information.
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LINKS
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MATHEMATICA
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QuadPrimes2[2, 0, 27, 10000] (* see A106856 *)
With[{nn=50}, Take[Union[Select[2#[[1]]+27#[[2]]&/@(Tuples[Range[ 0, nn], 2]^2), PrimeQ]], nn]] (* Harvey P. Dale, Jun 15 2014 *)
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PROG
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(PARI) list(lim)=my(v=List(), w, t); for(x=1, sqrtint(lim\2), w=2*x^2; for(y=0, sqrtint((lim-w)\27), if(isprime(t=w+27*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 09 2017
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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