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A087090 Positive numbers n such that p=n^2+n+41 and p+2 are twin primes. 2
0, 5, 12, 15, 17, 20, 24, 35, 45, 50, 59, 75, 90, 92, 105, 110, 119, 120, 132, 134, 167, 174, 182, 222, 225, 230, 264, 269, 285, 320, 335, 339, 362, 365, 372, 390, 419, 434, 437, 455, 462, 470, 479, 495, 539, 540, 549, 572, 594, 705, 710, 714, 759, 785, 789 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Pierre CAMI and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 2028 terms from Cami)

EXAMPLE

5 is in the sequence because 71 and 73 are twin primes.

MATHEMATICA

Select[Range[0, 800], AllTrue[#^2 +#+{41, 43}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, May 20 2016 *)

PROG

(PARI) isok(n) = isprime(n^2+n+41) && isprime(n^2+n+43); \\ Michel Marcus, Oct 03 2013

CROSSREFS

Cf. A007634, A087091.

Sequence in context: A009824 A286276 A314273 * A161756 A314274 A184399

Adjacent sequences:  A087087 A087088 A087089 * A087091 A087092 A087093

KEYWORD

nonn

AUTHOR

Zak Seidov, Aug 08 2003

STATUS

approved

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Last modified October 20 17:42 EDT 2019. Contains 328268 sequences. (Running on oeis4.)