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A139924
Primes of the form 8x^2+8xy+41y^2.
2
41, 89, 137, 281, 353, 401, 449, 593, 617, 761, 929, 977, 1097, 1217, 1289, 1409, 1553, 1601, 1697, 1721, 1913, 2153, 2273, 2633, 2657, 2777, 2801, 2897, 2969, 3089, 3209, 3257, 3593, 3833, 3881, 4049, 4217, 4337, 4409, 4457, 4649, 4673
OFFSET
1,1
COMMENTS
Discriminant=-1248. See A139827 for more information.
Also primes of the forms 32x^2+16xy+41y^2 and 20x^2+12xy+33y^2. See A140633. - T. D. Noe, May 19 2008
In base 12, the sequence is 35, 75, E5, 1E5, 255, 295, 315, 415, 435, 535, 655, 695, 775, 855, 8E5, 995, X95, E15, E95, EE5, 1135, 12E5, 1395, 1635, 1655, 1735, 1755, 1815, 1875, 1955, 1X35, 1X75, 20E5, 2275, 22E5, 2415, 2535, 2615, 2675, 26E5, 2835, 2855. Moreover, the discriminant is 880 and all primes are {35, 75, E5, 115, 1E5, 215} mod 220. - Walter Kehowski, May 31 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 {41, 89, 137, 161, 281, 305} (mod 312).
MATHEMATICA
QuadPrimes2[8, -8, 41, 10000] (* see A106856 *)
PROG
(Magma) [ p: p in PrimesUpTo(6000) | p mod 312 in [41, 89, 137, 161, 281, 305]]; // Vincenzo Librandi, Aug 01 2012
CROSSREFS
Sequence in context: A241081 A188173 A142411 * A155572 A356246 A107145
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 02 2008
STATUS
approved