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A139880
Primes of the form 13x^2+2xy+13y^2.
3
13, 61, 157, 181, 229, 349, 397, 661, 733, 829, 853, 997, 1021, 1069, 1237, 1669, 1693, 1741, 1861, 2029, 2341, 2677, 2749, 2917, 3037, 3181, 3253, 3373, 3517, 3541, 3709, 3853, 3877, 4021, 4093, 4261, 4357, 4549, 4597, 4861, 4933, 5101
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OFFSET
1,1
COMMENTS
Discriminant=-672. See
A139827
for more information.
Also primes of the forms 13x^2+4xy+52y^2 and 13x^2+8xy+40y^2. See
A140633
. -
T. D. Noe
, May 19 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)
FORMULA
The primes are congruent to {13, 61, 157} (mod 168).
MATHEMATICA
Union[QuadPrimes2[13, 2, 13, 10000], QuadPrimes2[13, -2, 13, 10000]] (* see
A106856
*)
PROG
(Magma) [ p: p in PrimesUpTo(6000) | p mod 168 in {13, 61, 157}]; //
Vincenzo Librandi
, Jul 30 2012
CROSSREFS
Sequence in context:
A119151
A081589
A270449
*
A379896
A127876
A361657
Adjacent sequences:
A139877
A139878
A139879
*
A139881
A139882
A139883
KEYWORD
nonn
,
easy
AUTHOR
T. D. Noe
, May 02 2008
STATUS
approved