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%I #10 May 05 2023 14:56:55
%S 2,5,7,13,47,103,107,127,163,233,293,337,383,433,443,467,503,673,677,
%T 733,797,877,1087,1093,1153,1217,1223,1307,1637,1933,2053,2087,2137,
%U 2423,2477,2543,2633,2687,2857,2917,3163,3373,3407,3467,3767,3793,3877
%N Primes p such that 8*p-3 and 8*p+3 are also prime numbers.
%C Subsequence of A023229. [_R. J. Mathar_, Aug 26 2009]
%C Primes of the form A087695(k)/8. [_R. J. Mathar_, Aug 26 2009]
%H Vincenzo Librandi, <a href="/A164570/b164570.txt">Table of n, a(n) for n = 1..1000</a>
%e For p=2, 8*2-3=13 and 8*2+3=19 are prime numbers, which adds p=2 to the sequence
%e For p=5, 8*5-3=37 and 8*5+3=43 are prime numbers, which adds p=5 to the sequence.
%t lst={};Do[p=Prime[n];If[PrimeQ[8*p-3]&&PrimeQ[8*p+3],AppendTo[lst,p]], {n,7!}];lst
%t Select[Prime[Range[1000]], And@@PrimeQ/@{8 # + 3, 8 # - 3}&] (* _Vincenzo Librandi_, Apr 09 2013 *)
%t Select[Prime[Range[1000]],AllTrue[8#+{3,-3},PrimeQ]&] (* _Harvey P. Dale_, May 05 2023 *)
%o (Magma) [p: p in PrimesUpTo(3000) | IsPrime(8*p-3) and IsPrime(8*p+3)]; // _Vincenzo Librandi_, Apr 09 2013
%Y Cf. A023212, A023217, A023224, A023230, A023239, A060212, A106015, A124098, A125272, A127430, A153768, A164566, A164567, A164568, A164569.
%K nonn,easy
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Aug 16 2009
%E Comments turned into examples by _R. J. Mathar_, Aug 26 2009
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