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Primes of the form 41x^2+38xy+41y^2.
3

%I #17 Sep 08 2022 08:45:34

%S 41,281,569,761,809,1289,1361,1481,1601,1889,2081,2129,2441,2609,2801,

%T 2969,3209,3329,3449,3761,3929,4001,4241,4289,4649,4721,5081,5441,

%U 5849,6089,6569,6761,8081,8609,8681,9041,9209,9281,9521,9929,10529

%N Primes of the form 41x^2+38xy+41y^2.

%C Discriminant=-5280. See A139827 for more information.

%C Also primes of the forms 41x^2+6xy+129y^2 and 41x^2+10xy+65y^2. See A140633. - _T. D. Noe_, May 19 2008

%H Vincenzo Librandi and Ray Chandler, <a href="/A140013/b140013.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)

%F The primes are congruent to {41, 161, 281, 329, 569, 689, 761, 809, 1121, 1289} (mod 1320).

%t Union[QuadPrimes2[41, 38, 41, 10000], QuadPrimes2[41, -38, 41, 10000]] (* see A106856 *)

%o (Magma) [ p: p in PrimesUpTo(11000) | p mod 1320 in {41, 161, 281, 329, 569, 689, 761, 809, 1121, 1289} ]; // _Vincenzo Librandi-, Aug 05 2012

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 02 2008