A139507 Primes of the form x^2 + 27x*y + y^2 for x and y nonnegative.

29, 59, 199, 239, 281, 349, 419, 431, 439, 521, 571, 631, 719, 811, 821, 919, 941, 1009, 1019, 1021, 1039, 1069, 1151, 1231, 1301, 1321, 1459, 1579, 1789, 1831, 1861, 1889, 1949, 1979, 2029, 2039, 2089, 2111, 2141, 2269, 2311, 2411, 2441, 2609, 2659, 2789

Offset: 1

Author

Artur Jasinski, Apr 24 2008

Keywords

• nonn

Links

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

Crossrefs

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

Programs

Mathematica

a = {}; w = 27; k = 1; Do[Do[If[PrimeQ[n^2 + w*n*m + k*m^2], AppendTo[a, n^2 + w*n*m + k*m^2]], {n, m, 400}], {m, 1, 400}]; Union[a] (*Artur Jasinski*)