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A131578 Numbers n such that p(n)^2-p(n)-1 and p(n)^2-p(n)+1 are twin primes with p(i)=i-th prime. 1

%I #6 Jan 12 2016 17:35:43

%S 2,4,19,34,75,88,197,221,244,247,272,278,322,375,383,399,560,573,604,

%T 618,690,741,834,1135,1193,1212,1228,1272,1382,1401,1490,1524,1585,

%U 1589,1779,1989

%N Numbers n such that p(n)^2-p(n)-1 and p(n)^2-p(n)+1 are twin primes with p(i)=i-th prime.

%H Harvey P. Dale, <a href="/A131578/b131578.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[2000],AllTrue[Prime[#]^2-Prime[#]+{1,-1},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Jan 12 2016 *)

%K nonn

%O 1,1

%A _Pierre CAMI_, Aug 29 2007

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)