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A236763 Numbers n such that n^4 - n +/- 1 are twin primes. 2
6, 9, 13, 16, 39, 60, 79, 174, 183, 198, 295, 361, 393, 481, 540, 669, 705, 715, 765, 781, 889, 975, 1078, 1149, 1218, 1260, 1288, 1294, 1351, 1363, 1503, 1600, 1611, 1701, 1713, 1911, 2041, 2254, 2298, 2484, 2553, 2625, 2899, 2946, 2959 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

975^4-975+1 (903687889651) and 975^4-975-1 (903687889649) are twin primes. Thus, 975 is a member of this sequence.

MATHEMATICA

Select[Range[3000], AllTrue[#^4-#+{1, -1}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 27 2014 *)

PROG

(Python)

import sympy

from sympy import isprime

{print(n) for n in range(10**4) if isprime(n**4-n+1) and isprime(n**4-n-1)}

(PARI)

s=[]; for(n=1, 3000, if(isprime(n^4-n+1)&&isprime(n^4-n-+1), s=concat(s, n))); s \\ Colin Barker, Jan 31 2014

CROSSREFS

Intersection of A236761 and A126424.

Sequence in context: A284800 A242295 A064799 * A030499 A181428 A171575

Adjacent sequences:  A236760 A236761 A236762 * A236764 A236765 A236766

KEYWORD

nonn

AUTHOR

Derek Orr, Jan 30 2014

STATUS

approved

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Last modified September 21 22:00 EDT 2019. Contains 327283 sequences. (Running on oeis4.)