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Primes of the form 9x^2 + 10y^2.
2

%I #18 Feb 10 2017 14:45:53

%S 19,241,331,499,571,601,691,739,769,1009,1129,1249,1291,1531,1579,

%T 1699,2011,2089,2131,2161,2521,2689,2731,2851,2971,3001,3049,3259,

%U 3331,3499,3691,3739,3889,4051,4129,4219,4339,4441,4561,4729,4801

%N Primes of the form 9x^2 + 10y^2.

%C Discriminant = -360. See A107132 for more information.

%H Vincenzo Librandi and Ray Chandler, <a href="/A107203/b107203.txt">Table of n, a(n) for n = 1..10000</a> [First 1000 terms from Vincenzo Librandi]

%H 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 QuadPrimes2[9, 0, 10, 10000] (* see A106856 *)

%o (PARI) list(lim)=my(v=List(),w,t); for(x=1, sqrtint(lim\9), w=9*x^2; for(y=1, sqrtint((lim-w)\10), if(isprime(t=w+10*y^2), listput(v,t)))); Set(v) \\ _Charles R Greathouse IV_, Feb 10 2017

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 13 2005