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%I #40 Jun 21 2022 16:59:36
%S 3,11,17,23,41,47,53,59,83,89,107,131,137,173,179,191,251,257,263,293,
%T 311,317,347,353,359,389,401,419,443,467,479,503,521,557,587,593,599,
%U 641,653,719,809,839,857,863,887,947,971,977,1013,1019,1031,1049,1097
%N Primes p such that p+20 is also prime.
%H Seiichi Manyama, <a href="/A153419/b153419.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Vincenzo Librandi)
%e 3 is in the sequence because 3+20=23 is prime; 11 is in the sequence because 11+20=31 is prime.
%p for a from 1 to 140 do if isprime(a) and isprime(a+20) then print(a)
%p end if; end do; # _Matt C. Anderson_, Jun 20 2022
%t Select[Prime[Range[200]], PrimeQ[(# + 20)]&] (* _Vincenzo Librandi_, Apr 14 2013 *)
%o (Magma) [p: p in PrimesUpTo(1100) | IsPrime(p + 20)]; // _Vincenzo Librandi_, Apr 14 2013
%Y Cf. A153417, A049488, A153418.
%K nonn,easy
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Dec 25 2008
%E Definition improved from _Bruno Berselli_, Oct 31 2012
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