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A139499 Primes of the form x^2 + 19x*y + y^2 for x and y nonnegative. 1
43, 67, 127, 151, 331, 373, 421, 457, 463, 613, 631, 739, 757, 883, 919, 967, 1033, 1087, 1171, 1327, 1381, 1429, 1453, 1471, 1549, 1579, 1597, 1747, 1759, 1789, 1801, 2053, 2083, 2143, 2269, 2293, 2311, 2347, 2389, 2473, 2503, 2671, 2767, 2797, 2857 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)
MATHEMATICA
a = {}; w = 19; 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*)
upto=3000; With[{max=Ceiling[Sqrt[upto]]}, Select[Union[Select[(First[#]^2+ 19First[#]Last[#]+ Last[#]^2)&/@(Tuples[Range[0, max], {2}]), PrimeQ]], #<+upto&]] (* Harvey P. Dale, Jul 20 2011 *)
CROSSREFS
Sequence in context: A039385 A043208 A043988 * A201688 A174022 A033229
KEYWORD
nonn
AUTHOR
Artur Jasinski, Apr 24 2008
STATUS
approved

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Last modified July 15 02:08 EDT 2024. Contains 374323 sequences. (Running on oeis4.)