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A106866 Primes of the form 2x^2+xy+3y^2, with x and y nonnegative. 3

%I #21 Aug 22 2019 08:04:03

%S 2,3,13,41,71,127,139,179,257,269,311,331,409,439,443,461,541,587,673,

%T 739,761,823,887,967,1051,1061,1087,1129,1153,1223,1237,1277,1373,

%U 1381,1409,1427,1439,1567,1619,1733,1741,1783,1933,1973,2017,2063

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

%C Discriminant=-23.

%C For even x we generate A309139. - _R. J. Mathar_, Aug 22 2019

%H Vincenzo Librandi and Ray Chandler, <a href="/A106866/b106866.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[2, 1, 3, 10000] (* see A106856 *)

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 09 2005

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Last modified April 18 06:24 EDT 2024. Contains 371769 sequences. (Running on oeis4.)