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A106866 Primes of the form 2x^2+xy+3y^2, with x and y nonnegative. 3
2, 3, 13, 41, 71, 127, 139, 179, 257, 269, 311, 331, 409, 439, 443, 461, 541, 587, 673, 739, 761, 823, 887, 967, 1051, 1061, 1087, 1129, 1153, 1223, 1237, 1277, 1373, 1381, 1409, 1427, 1439, 1567, 1619, 1733, 1741, 1783, 1933, 1973, 2017, 2063 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant=-23.

For even x we generate A309139. - R. J. Mathar, Aug 22 2019

LINKS

Vincenzo Librandi and Ray Chandler, Table of n, a(n) for n = 1..10000 [First 1000 terms from Vincenzo Librandi]

N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

MATHEMATICA

QuadPrimes2[2, 1, 3, 10000] (* see A106856 *)

CROSSREFS

Sequence in context: A117528 A264042 A122719 * A278139 A280005 A235626

Adjacent sequences:  A106863 A106864 A106865 * A106867 A106868 A106869

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 09 2005

STATUS

approved

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Last modified October 15 07:38 EDT 2019. Contains 328026 sequences. (Running on oeis4.)