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 A140621 Primes of the form 28x^2+12xy+57y^2. 1
 73, 97, 193, 457, 577, 1033, 1657, 1753, 2017, 2113, 2137, 2377, 2593, 2953, 3217, 3313, 3673, 3697, 4153, 4297, 4513, 5233, 5857, 6073, 6337, 6793, 7057, 7417, 7753, 7873, 7993, 8353, 8377, 9433, 9817, 10177, 10753, 10993, 11113, 11497 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Discriminant=-6240. Also primes of the form 72x^2+48xy+73y^2. In base 12, the sequence is 61, 81, 141, 321, 401, 721, E61, 1021, 1201, 1281, 12X1, 1461, 1601, 1861, 1X41, 1E01, 2161, 2181, 24X1, 25X1, 2741, 3041, 3481, 3621, 3801, 3E21, 4101, 4361, 45X1, 4681, 4761, 4X01, 4X21, 5561, 5821, 5X81, 6281, 6441, 6521, 67X1, where X is for 10 and E is for 11. Moreover, the discriminant is -3740. - 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[28, 12, 57, 10000], QuadPrimes2[28, -12, 57, 10000]] (* see A106856 *) CROSSREFS Cf. A140633. Sequence in context: A155573 A107008 A141375 * A143577 A146354 A050958 Adjacent sequences:  A140618 A140619 A140620 * A140622 A140623 A140624 KEYWORD nonn,easy AUTHOR T. D. Noe, May 19 2008 STATUS approved

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Last modified July 27 20:33 EDT 2021. Contains 346308 sequences. (Running on oeis4.)