This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A118504 #17 Feb 08 2021 05:29:07
%S A118504 2,3,5,11,23,29,41,83,113,131,173,191,281,443,641,911,1013,1019,1031,
%T A118504 1103,1451,1499,1811,1901,2003,2063,2351,2399,2939,3299,3389,3413,
%U A118504 4793,4919,5051,5231,5279,5303,5501,5639,6113,6131,6269,6449,7079,7103,7121,7211
%N A118504 Sophie Germain primes whose sum of digits is also a Sophie Germain prime.
%H A118504 Amiram Eldar, <a href="/A118504/b118504.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Harvey P. Dale)
%e A118504 191 is in the sequence because it is a Sophie Germain prime and the sum of its digits 1+9+1 = 11 is also a Sophie Germain prime.
%t A118504 sgpQ[n_]:=Module[{c=Total[IntegerDigits[n]]},And@@PrimeQ[{2n+1,c,2c+1}]]; Select[Prime[Range[1000]],sgpQ] (* _Harvey P. Dale_, Oct 14 2012 *)
%Y A118504 Subsequence of A118571.
%Y A118504 Cf. A005384.
%K A118504 base,nonn
%O A118504 1,1
%A A118504 Luc Stevens (lms022(AT)yahoo.com), May 06 2006; corrected May 12 2006
%E A118504 Corrected by _T. D. Noe_, Oct 25 2006
%E A118504 Corrected by _Harvey P. Dale_, Oct 14 2012