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 A139530 Primes of the form 24n+13. 2

%I

%S 13,37,61,109,157,181,229,277,349,373,397,421,541,613,661,709,733,757,

%T 829,853,877,997,1021,1069,1093,1117,1213,1237,1381,1429,1453,1549,

%U 1597,1621,1669,1693,1741,1789,1861,1933,2029,2053,2221,2269,2293,2341,2389

%N Primes of the form 24n+13.

%C Primes of the form 4x^2+4xy+13y^2. Discriminant=-192. - _T. D. Noe_, May 02 2008

%C Also, primes of form u^2+12v^2 with odd v, while A107008 (which is also expressible as x^2+48y^2) has even v. One can transform its form as (2x+y)^2+12y^2 (where y can only be odd), while the second is x^2+12(2y)^2. Both sequences are 1 mod 12 and together they are primes x^2+12y^2 (A068228). [From _Tito Piezas III_, Jan 01 2009]

%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 a = {}; Do[If[PrimeQ[24 n + 13], AppendTo[a, 24 n + 13]], {n, 0, 200}]; a

%t Select[24Range[0,150]+13,PrimeQ] (* _Harvey P. Dale_, Mar 11 2011 *)

%Y Cf. A139827.

%K nonn

%O 1,1

%A _Artur Jasinski_, Apr 25 2008

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Last modified September 18 17:02 EDT 2020. Contains 337170 sequences. (Running on oeis4.)