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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 January 20 23:16 EST 2020. Contains 331104 sequences. (Running on oeis4.)