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 A005107 M5261 #19 Jan 13 2014 11:57:34
%S A005107 37,103,113,151,157,163,173,181,193,227,233,257,277,311,331,337,347,
%T A005107 353,379,389,397,401,409,421,457,463,467,487,491,521,523,541,547,569,
%U A005107 571,601,607,613,631,653,683,701,727,733,773,787,797,811,821,829,853,857
%N A005107 Class 3+ primes (for definition see A005105).
%D A005107 R. K. Guy, Unsolved Problems in Number Theory, A18.
%D A005107 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A005107 T. D. Noe, <a href="/A005107/b005107.txt">Table of n, a(n) for n=1..10000</a>
%p A005107 For Maple program see Mathar link in A005105.
%t A005107 PrimeFactors[n_Integer] := Flatten[ Table[ #[[1]], {1}] & /@ FactorInteger[n]]; f[n_Integer] := Block[{m = n}, If[m == 0, m = 1, While[ IntegerQ[m/2], m /= 2]; While[ IntegerQ[m/3], m /= 3]]; Apply[Times, PrimeFactors[m] + 1]]; ClassPlusNbr[n_] := Length[ NestWhileList[f, n, UnsameQ, All]] - 3; Prime[ Select[ Range[150], ClassPlusNbr[ Prime[ # ]] == 3 &]]
%Y A005107 Cf. A005113, A005105, A005106, A005108.
%K A005107 nonn
%O A005107 1,1
%A A005107 _N. J. A. Sloane_, _Simon Plouffe_
%E A005107 Edited and extended by _Robert G. Wilson v_, Mar 20 2003