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A140625
Primes of the form 28x^2+20xy+85y^2.
1
157, 277, 397, 613, 733, 757, 853, 997, 1213, 1453, 1597, 2053, 2437, 2557, 2677, 2797, 3037, 3253, 3733, 3877, 4357, 4813, 4957, 5077, 5413, 5557, 6277, 6637, 6733, 6997, 7237, 7573, 8053, 8293, 8893, 9013, 9277, 9397, 9733, 9973, 10093
OFFSET
1,1
COMMENTS
Discriminant=-9120. Also primes of the form 45x^2+30xy+157y^2.
In base 12, the sequence is 111, 1E1, 291, 431, 511, 531, 5E1, 6E1, 851, X11, E11, 1231, 14E1, 1591, 1671, 1751, 1911, 1X71, 21E1, 22E1, 2631, 2951, 2X51, 2E31, 3171, 3271, 3771, 3X11, 3X91, 4071, 4231, 4471, 47E1, 4971, 5191, 5271, 5451, 5531, 5771, 5931, 5X11, where X is 10 and E is 11. Moreover, the discriminant is -5340. - 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, 20, 85, 10000], QuadPrimes2[28, -20, 85, 10000]] (* see A106856 *)
CROSSREFS
Cf. A140633.
Sequence in context: A303094 A001837 A142581 * A142874 A346431 A234364
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 19 2008
STATUS
approved