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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
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
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 19 2008
STATUS
approved