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 A179002 #7 Mar 30 2012 18:52:41 %S A179002 2,7,19,31,37,43,61,67,79,97,107,109,151,157,163,199,223,241,257,269, %T A179002 271,307,337,349,379,409,421,433,439,523,557,577,601,613,619,631,673, %U A179002 691,739,757,787,811,823,853,863,877,883,919,967,991,1009,1051,1061,1063,1117,1153,1181,1213 %N A179002 Primes p such that 2^(2p-1) mod (2p+1) is prime. %F A179002 A178970(a(n)=A000040(i))=A000040(k). %t A179002 fQ[n_] := PrimeQ@ PowerMod[2, 2n - 1, 2n + 1]; Select[ Prime@ Range@ 200, fQ] %Y A179002 Cf. A000040, A178537, A178970. %K A179002 nonn %O A179002 1,1 %A A179002 _Juri-Stepan Gerasimov_, Jan 03 2011