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A140631 Primes of the form 57x^2+18xy+193y^2. 1
193, 457, 1033, 2017, 2137, 2377, 3217, 3313, 3697, 4153, 5233, 6073, 6337, 7057, 7417, 7753, 8353, 9433, 10753, 11113, 11617, 11953, 12097, 12433, 12553, 13297, 14737, 15073, 16417, 16633, 16993, 17257, 17977, 19273, 20113, 20353, 20857 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant=-43680. Also primes of the form 148x^2+132xy+177y^2.

In base 12, the sequence is 141, 321, 721, 1201, 12X1, 1461, 1X41, 1E01, 2181, 24X1, 3041, 3621, 3801, 4101, 4361, 45X1, 4X01, 5561, 6281, 6521, 6881, 6E01, 7001, 7241, 7321, 7841, 8641, 8881, 9601, 9761, 9X01, 9EX1, X4X1, E1X1, E781, E941, 100X1, where X is 10 and E is 11. Moreover, the discriminant is -21340. - Walter Kehowski, Jun 01 2008

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

Union[QuadPrimes2[57, 18, 193, 10000], QuadPrimes2[57, -18, 193, 10000]] (* see A106856 *)

CROSSREFS

Cf. A140633.

Sequence in context: A328137 A113000 A105129 * A142117 A142564 A174521

Adjacent sequences:  A140628 A140629 A140630 * A140632 A140633 A140634

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 19 2008

STATUS

approved

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Last modified September 27 22:36 EDT 2020. Contains 337388 sequences. (Running on oeis4.)