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A139948 Primes of the form 19x^2+4xy+19y^2. 2
19, 103, 223, 271, 307, 523, 727, 859, 1039, 1063, 1123, 1279, 1291, 1447, 1483, 1531, 1543, 1699, 1783, 1879, 1951, 1987, 2287, 2371, 2467, 2551, 2707, 2719, 2803, 2971, 3079, 3163, 3307, 3331, 3391, 3583, 3727, 3919, 4003, 4231, 4339 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant=-1428. See A139827 for more information.

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 {19, 55, 103, 115, 223, 271, 307, 355, 451, 475, 523, 535, 559, 727, 859, 871, 943, 1039, 1063, 1123, 1147, 1279, 1291, 1375} (mod 1428).

MATHEMATICA

Union[QuadPrimes2[19, 4, 19, 10000], QuadPrimes2[19, -4, 19, 10000]] (* see A106856 *)

PROG

(MAGMA) [ p: p in PrimesUpTo(6000) | p mod 1428 in [19, 55, 103, 115, 223, 271, 307, 355, 451, 475, 523, 535, 559, 727, 859, 871, 943, 1039, 1063, 1123, 1147, 1279, 1291, 1375]]; // Vincenzo Librandi, Aug 02 2012

CROSSREFS

Sequence in context: A300774 A054658 A023296 * A101010 A201854 A195460

Adjacent sequences:  A139945 A139946 A139947 * A139949 A139950 A139951

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 02 2008

STATUS

approved

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Last modified May 26 13:59 EDT 2022. Contains 354092 sequences. (Running on oeis4.)