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A140007 Primes of the form 20x^2+20xy+71y^2. 1
71, 191, 311, 599, 719, 839, 911, 1439, 1511, 1871, 2039, 2399, 2711, 3191, 3359, 3719, 4079, 4271, 4679, 4799, 4871, 5039, 5351, 5399, 5471, 5591, 5879, 6359, 6719, 6791, 6911, 7151, 8039, 8111, 8231, 8831, 8999, 9311, 9431, 9551, 9791 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant = -5280. 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 {71, 119, 191, 311, 551, 599, 719, 839, 911, 1079} (mod 1320).

MATHEMATICA

QuadPrimes2[20, -20, 71, 10000] (* see A106856 *)

PROG

(MAGMA) [p: p in PrimesUpTo(12000) | p mod 1320 in [71, 119, 191, 311, 551, 599, 719, 839, 911, 1079]]; // Vincenzo Librandi, Aug 04 2012

CROSSREFS

Sequence in context: A142612 A295835 A139991 * A023107 A174370 A174454

Adjacent sequences:  A140004 A140005 A140006 * A140008 A140009 A140010

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 02 2008

STATUS

approved

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Last modified November 28 13:47 EST 2021. Contains 349413 sequences. (Running on oeis4.)