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A140619 Primes of the form 19x^2+4xy+28y^2. 2
19, 43, 139, 211, 283, 307, 523, 547, 571, 739, 787, 811, 1051, 1459, 1531, 1579, 1627, 1723, 1867, 1987, 2131, 2251, 2371, 2659, 2683, 2851, 3163, 3187, 3307, 3571, 3643, 3691, 3739, 3907, 4003, 4099, 4219, 4243, 4363, 4483, 4507, 5011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant=-2112. Also primes of the form 19x^2+10xy+43y^2.

In base 12, the sequence is 17, 37, E7, 157, 1E7, 217, 377, 397, 3E7, 517, 557, 577, 737, X17, X77, XE7, E37, EE7, 10E7, 1197, 1297, 1377, 1457, 1657, 1677, 1797, 19E7, 1X17, 1XE7, 2097, 2137, 2177, 21E7, 2317, 2397, 2457, 2537, 2557, 2637, 2717, 2737, 2X97, where X is for 10 and E is for 11. Moreover, the discriminant is -1280. - 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[19, 4, 28, 10000], QuadPrimes2[19, -4, 28, 10000]] (* see A106856 *)

CROSSREFS

Cf. A140633.

Sequence in context: A165567 A205533 A185167 * A229765 A058829 A063313

Adjacent sequences:  A140616 A140617 A140618 * A140620 A140621 A140622

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 19 2008

STATUS

approved

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Last modified July 5 19:02 EDT 2020. Contains 335473 sequences. (Running on oeis4.)