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A106919 Primes of the form 3x^2+xy+5y^2, with x and y any integer. 1
3, 5, 7, 19, 29, 41, 53, 79, 107, 127, 137, 167, 181, 193, 199, 239, 241, 251, 257, 263, 271, 277, 281, 293, 307, 311, 331, 359, 379, 433, 449, 487, 491, 499, 523, 557, 577, 593, 599, 607, 617, 619, 643, 647, 653, 661, 709, 757, 761, 829, 853, 877, 883, 907 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Discriminant=-59. See A106856 for more information.

Primes p such that the polynomial x^3-2x^2-1 is irreducible over Zp. The polynomial discriminant is also -59. - T. D. Noe (noe(AT)sspectra.com), May 13 2005

MATHEMATICA

f[x_, y_]:=3*x^2+x*y+5*y^2; lst={}; Do[Do[p=f[x, y]; If[PrimeQ[p], AppendTo[lst, p]], {y, -5!, 6!}], {x, -5!, 6!}]; Take[Union[lst], 5! ] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jul 04 2009]

Union[QuadPrimes[3, 1, 5, 10000], QuadPrimes[3, -1, 5, 10000]] (* see A106856 *)

CROSSREFS

Sequence in context: A184805 A079131 A179687 * A005850 A052334 A154526

Adjacent sequences:  A106916 A106917 A106918 * A106920 A106921 A106922

KEYWORD

nonn,easy

AUTHOR

T. D. Noe (noe(AT)sspectra.com), May 09 2005

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Last modified February 15 08:17 EST 2012. Contains 205727 sequences.