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A107144 Primes of the form 5x^2+8y^2. +0
4
5, 13, 37, 53, 157, 173, 197, 277, 293, 317, 373, 397, 557, 613, 653, 677, 733, 757, 773, 797, 853, 877, 997, 1013, 1093, 1117, 1213, 1237, 1277, 1373, 1453, 1493, 1597, 1613, 1637, 1693, 1733, 1877, 1933, 1973, 1997, 2053, 2213, 2237, 2293 (list; graph; listen)
OFFSET

1,1

COMMENT

Discriminant=-160. See A107132 for more information.

Except for 5, also primes of the form 13x^2+8xy+32y^2. See A140633. - T. D. Noe (noe(AT)sspectra.com), May 19 2008

FORMULA

Except for 5, the primes are congruent to {13, 37} (mod 40). - T. D. Noe (noe(AT)sspectra.com), May 02 2008

MATHEMATICA

Clear[f, lst, p, x, y]; f[x_, y_]:=5*x^2+8*y^2; lst={}; Do[Do[p=f[x, y]; If[PrimeQ[p]&&p<18414, AppendTo[lst, p]], {y, 0, 60}], {x, 0, 70}]; Take[Union[lst], 260] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Aug 05 2009]

QuadPrimes[5, 0, 8, 10000] (* see A106856 *)

CROSSREFS

Cf. A139827.

Sequence in context: A167710 A126359 A141408 this_sequence A137815 A089523 A058507

Adjacent sequences: A107141 A107142 A107143 this_sequence A107145 A107146 A107147

KEYWORD

nonn,easy

AUTHOR

T. D. Noe (noe(AT)sspectra.com), May 13 2005

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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