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A236760
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Numbers n such that n^4 + n +- 1 are twin primes.
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2
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2, 6, 9, 12, 26, 44, 72, 77, 119, 204, 266, 290, 351, 506, 539, 542, 561, 644, 741, 807, 861, 924, 992, 996, 1016, 1032, 1049, 1356, 1412, 1556, 1640, 1794, 1847, 1862, 1871, 1895, 1980, 2036, 2129, 2222, 2289, 2354, 2445, 2616, 2630
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OFFSET
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1,1
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LINKS
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EXAMPLE
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992^4 + 992 + 1 (968381957089) and 992^4 + 992 - 1 (968381957087) are twin primes. Thus, 992 is a member of this sequence.
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MATHEMATICA
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Select[Range[3000], PrimeQ[#^4 + # - 1] && PrimeQ[#^4 + # + 1] &] (* Vincenzo Librandi, Dec 26 2015 *)
Select[Range[3000], AllTrue[#^4+#+{1, -1}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 13 2017 *)
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PROG
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(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
(Magma) [n: n in [1..5*10^3] |IsPrime(n^4+n-1) and IsPrime(n^4 +n+1)]; // Vincenzo Librandi, Dec 26 2015
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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