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%I #13 Sep 08 2022 08:45:07
%S 1,3,4,8,10,14,15,16,17,18,21,27,36,41,45,47,48,50,62,67,71,83,85,94,
%T 95,96,102,105,106,118,125,129,133,136,153,154,155,157,159,160,171,
%U 176,201,202,205,212,214,231,237,246,254,258,259,263,269,270,271,276,278
%N Numbers n such that 210*n -/+ 13 are primes.
%H Vincenzo Librandi, <a href="/A075751/b075751.txt">Table of n, a(n) for n = 1..1000</a>
%e n=1: 210*1-13=197 and 210*1+13=223 are primes.
%t Select[Range[1, 300], PrimeQ[210 # - 13]&&PrimeQ[210 # + 13]&] (* _Vincenzo Librandi_, Oct 05 2013 *)
%o (PARI) isok(n) = isprime(210*n+13) && isprime(210*n-13); \\ _Michel Marcus_, Oct 03 2013
%o (Magma) [n: n in [1..350] | IsPrime(210*n-13) and IsPrime(210*n+13)]; // _Vincenzo Librandi_, Oct 05 2013
%K easy,nonn
%O 1,2
%A _Zak Seidov_, Oct 08 2002
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