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