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 A139502 Primes of the form x^2 + 22x*y + y^2 for x and y nonnegative. 5

%I

%S 241,409,601,769,1009,1129,1201,1249,1321,1489,1609,1801,2089,2161,

%T 2281,2521,2689,3001,3049,3121,3169,3361,3529,3769,3889,4129,4201,

%U 4441,4561,4729,4801,4969,5209,5281,5449,5521,5569,5641,5689,5881,6121,6361,6481

%N Primes of the form x^2 + 22x*y + y^2 for x and y nonnegative.

%C Also primes of the form x^2 + 120y^2. - _T. D. Noe_, Apr 29 2008

%C Also primes of the form x^2+240y^2. See A140633. - _T. D. Noe_, May 19 2008

%C In base 12, the sequence is 181, 2X1, 421, 541, 701, 7X1, 841, 881, 921, X41, E21, 1061, 1261, 1301, 13X1, 1561, 1681, 18X1, 1921, 1981, 1X01, 1E41, 2061, 2221, 2301, 2481, 2521, 26X1, 2781, 28X1, 2941, 2X61, 3021, 3081, 31X1, 3241, 3281, 3321, 3361, 34X1, 3661, 3821, 3901, where X is 10 and E is 11. Moreover, the discriminant is 340. - _Walter Kehowski_, Jun 01 2008

%H Vincenzo Librandi, <a href="/A139502/b139502.txt">Table of n, a(n) for n = 1..1000</a>

%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 {1, 49} (mod 120). - _T. D. Noe_, Apr 29 2008

%t QuadPrimes2[1, 0, 120, 10000] (* see A106856 *)

%o (MAGMA) [ p: p in PrimesUpTo(7000) | p mod 120 in {1, 49}]; // _Vincenzo Librandi_, Jul 28 2012

%Y Cf. A139489, A007645, A068228, A007519, A033212, A033212, A107152, A107008, A033215, A107145, A139490, A139491.

%Y Cf. A139643.

%K nonn,easy

%O 1,1

%A _Artur Jasinski_, Apr 24 2008

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Last modified August 25 21:00 EDT 2019. Contains 326324 sequences. (Running on oeis4.)