%I A106865
%S A106865 2,3,7,23,43,47,67,83,103,107,127,163,167,223,227,263,283,307,347,367,
%T A106865 383,443,463,467,487,503,523,547,563,587,607,643,647,683,727,743,787,
%U A106865 823,827,863,883,887,907,947,967,983,1063,1087,1103,1123,1163,1187
%N A106865 Primes of the form 2x^2-2xy+3y^2, with x and y nonnegative.
%C A106865 Discriminant=-20. See A106856 for more information.
%C A106865 Primes congruent to 2,3,7 modulo 20. - Michael Somos Aug 13 2006
%t A106865 f[x_,y_]:=2*x^2+2*x*y+3*y^2; lst={};Do[Do[p=f[x,y];If[PrimeQ[p],AppendTo[lst,
p]],{y,-5!,6!}],{x,-5!,6!}];Take[Union[lst],5! ] [From Vladimir Orlovsky
(4vladimir(AT)gmail.com), Jul 06 2009]
%t A106865 QuadPrimes[2, -2, 3, 10000] (* see A106856 *)
%Y A106865 For n>1, a(n) = A122870[n-1].
%Y A106865 Sequence in context: A059661 A072686 A002230 this_sequence A000057 A037231
A082449
%Y A106865 Adjacent sequences: A106862 A106863 A106864 this_sequence A106866 A106867
A106868
%K A106865 nonn,easy
%O A106865 1,1
%A A106865 T. D. Noe (noe(AT)sspectra.com), May 09 2005
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