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A075752 210*n -/+ 17 ares both primes. 1

%I

%S 1,3,4,7,8,9,22,26,32,42,45,46,52,56,57,58,62,70,75,79,81,84,86,87,96,

%T 99,100,101,103,111,129,139,142,143,146,166,178,179,185,191,196,200,

%U 201,202,216,217,234,235,240,241,252,253,260,265,267,276,294,295,298

%N 210*n -/+ 17 ares both primes.

%H Vincenzo Librandi, <a href="/A075752/b075752.txt">Table of n, a(n) for n = 1..1000</a>

%e n=1: 210*1-17=193 and 210*1+17=227 are primes.

%t Select[Range[1, 300], PrimeQ[210 # - 17]&&PrimeQ[210 # + 17]&] (* _Vincenzo Librandi_, Oct 05 2013 *)

%o (PARI) isok(n) = isprime(210*n+17) && isprime(210*n-17); \\ _Michel Marcus_, Oct 03 2013

%o (MAGMA) [n: n in [1..350] | IsPrime(210*n-17) and IsPrime(210*n+17)]; // _Vincenzo Librandi_, Oct 05 2013

%K easy,nonn

%O 1,2

%A _Zak Seidov_, Oct 08 2002

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Last modified August 9 05:12 EDT 2020. Contains 336319 sequences. (Running on oeis4.)