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%I A140618 #20 Aug 05 2014 14:16:31
%S A140618 23,47,191,239,263,311,359,479,503,647,719,1031,1103,1151,1223,1487,
%T A140618 1559,1583,1607,1847,1871,2039,2063,2087,2399,2543,2591,2927,2999,
%U A140618 3407,3671,3767,3863,3911,4007,4127,4463,4583,4679,4751,4799,4871
%N A140618 Primes of the form 20x^2+4xy+23y^2.
%C A140618 Discriminant=-1824. Also primes of the form 23x^2+20xy+44y^2.
%C A140618 In base 12, the sequence is 1E, 3E, 13E, 17E, 19E, 21E, 25E, 33E, 35E, 45E, 4EE, 71E, 77E, 7EE, 85E, X3E, X9E, XEE, E1E, 109E, 10EE, 121E, 123E, 125E, 147E, 157E, 15EE, 183E, 189E, 1E7E, 215E, 221E, 229E, 231E, 239E, 247E, 26EE, 279E, 285E, 28EE, 293E, 299E, where X is for 10 and E is for 11. Moreover, the discriminant is -1080. - _Walter Kehowski_, May 31 2008
%H A140618 Vincenzo Librandi and Ray Chandler, <a href="/A140618/b140618.txt">Table of n, a(n) for n = 1..10000</a> [First 1000 terms from Vincenzo Librandi]
%H A140618 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 A140618 Union[QuadPrimes220, 4, 23, 10000], QuadPrimes2[20, -4, 23, 10000]] (* see A106856 *)
%Y A140618 Cf. A140633.
%K A140618 nonn,easy
%O A140618 1,1
%A A140618 _T. D. Noe_, May 19 2008

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