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A106879 Primes of the form 3x^2-xy+3y^2, with x and y nonnegative. 1


%S 3,5,13,47,73,103,167,227,283,293,353,367,383,433,467,503,563,577,593,

%T 677,727,797,853,857,997,1063,1097,1123,1153,1193,1217,1237,1433,1447,

%U 1543,1553,1567,1627,1657,1697,1823,1847,1867,1973,1987,1993,2063

%N Primes of the form 3x^2-xy+3y^2, with x and y nonnegative.

%C Discriminant=-35.

%H Vincenzo Librandi and Ray Chandler, <a href="/A106879/b106879.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[3, -1, 3, 10000] (* see A106856 *)

%Y Cf. A106878.

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 09 2005

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Last modified December 3 17:23 EST 2021. Contains 349467 sequences. (Running on oeis4.)