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%I A107140 #18 Feb 09 2017 14:33:28
%S A107140 5,7,73,83,157,257,383,433,523,563,587,647,727,853,857,887,1013,1063,
%T A107140 1097,1153,1237,1567,1613,1627,1697,1777,1847,2063,2203,2273,2393,
%U A107140 2467,2707,2803,2887,2897,2917,3167,3407,3433,3643,3673,3727,3793
%N A107140 Primes of the form 5x^2 + 7y^2.
%C A107140 Discriminant = -140. See A107132 for more information.
%H A107140 Vincenzo Librandi and Ray Chandler, <a href="/A107140/b107140.txt">Table of n, a(n) for n = 1..10000</a> [First 1000 terms from Vincenzo Librandi]
%H A107140 N. J. A. Sloane et al., <a href="https://oeis.org/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a> (Index to related sequences, programs, references)
%t A107140 QuadPrimes2[5, 0, 7, 10000] (* see A106856 *)
%o A107140 (PARI) list(lim)=my(v=List(),w,t); for(x=0, sqrtint(lim\5), w=5*x^2; for(y=0, sqrtint((lim-w)\7), if(isprime(t=w+7*y^2), listput(v,t)))); Set(v) \\ _Charles R Greathouse IV_, Feb 09 2017
%K A107140 nonn,easy
%O A107140 1,1
%A A107140 _T. D. Noe_, May 13 2005

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