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%I #12 Sep 08 2022 08:45:07
%S 2,3,5,7,9,10,13,17,26,29,34,45,48,54,57,59,60,61,63,75,82,89,108,112,
%T 113,123,133,136,139,140,146,147,148,150,151,153,156,166,167,172,173,
%U 174,175,177,184,185,195,208,210,215,227,245,250,265,266,269,278,279
%N 210*n -/+ 11 are primes.
%H Vincenzo Librandi, <a href="/A075750/b075750.txt">Table of n, a(n) for n = 1..1000</a>
%e n=2: 210*2-11=409 and 210*2+11=431 are primes.
%t Select[Range[1, 300], PrimeQ[210 # - 11]&&PrimeQ[210 # + 11] &] (* _Vincenzo Librandi_, Oct 05 2013 *)
%o (PARI) isok(n) = isprime(210*n+11) && isprime(210*n-11); \\ _Michel Marcus_, Oct 03 2013
%o (Magma) [n: n in [1..350] | IsPrime(210*n-11) and IsPrime(210*n+11)]; // _Vincenzo Librandi_, Oct 05 2013
%K easy,nonn
%O 1,1
%A _Zak Seidov_, Oct 08 2002