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A140628
Primes of the form 39x^2+6xy+71y^2.
1
71, 239, 311, 599, 719, 1151, 1319, 1439, 1511, 1559, 1871, 2111, 2879, 2999, 3359, 3719, 3911, 4079, 4271, 4751, 4871, 5039, 5279, 5591, 5639, 6311, 6719, 6791, 6959, 7079, 8039, 8951, 8999, 9239, 9431, 9479, 9551, 9719, 9791, 9839, 10151
OFFSET
1,1
COMMENTS
Discriminant=-11040. Also primes of the form 71x^2+70xy+95y^2.
In base 12, the sequence is 5E, 17E, 21E, 41E, 4EE, 7EE, 91E, 9EE, X5E, X9E, 10EE, 127E, 17EE, 189E, 1E3E, 219E, 231E, 243E, 257E, 28EE, 299E, 2XEE, 307E, 329E, 331E, 379E, 3X7E, 3E1E, 403E, 411E, 479E, 521E, 525E, 541E, 555E, 559E, 563E, 575E, 57EE, 583E, 5X5E, where X is 10 and E is 11. Moreover, the discriminant is -6480. - 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[39, 6, 71, 10000], QuadPrimes2[39, -6, 71, 10000]] (* see A106856 *)
CROSSREFS
Cf. A140633.
Sequence in context: A159472 A160369 A001126 * A123038 A325079 A142325
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 19 2008
STATUS
approved