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 A127557 #2 Mar 31 2012 10:22:03
%S A127557 5,0,1,8,8,6,5,6,5,7,3,7,7,3,7,8,2,3,3,7,1,4,1,5,6,2,8,3,1,8,1,1,3,6,
%T A127557 8,6,8,1,3,3,8,9,4,1,7,7,1,4,7,9,8,0,0,5,7,1,0,3,8,2,7,6,1,9,8,0,4,1,
%U A127557 2,6,4,7,8,3,6,2,0,2,4,8,2,0,2,4,6,5,5,7,9,5,9,7,7,9,6,2,0,7,6,0
%N A127557 Decimal expansion of the number 5.018865657377378233714156283... having continued fraction expansion 5, 53, 157, 173, 211, 257, 263, 373, 563, ... (balanced primes order one A006562).
%t A127557 a = {}; Do[If[PrimeQ[((Prime[n + 2] + Prime[n + 1])/2 + (Prime[n + 1] + Prime[n])/2)/2], AppendTo[a, ((Prime[n + 2] + Prime[n + 1])/2 + (Prime[n + 1] + Prime[n])/2)/2]], {n, 1, 1000}]; RealDigits[N[FromContinuedFraction[a], 100]][[1]]
%Y A127557 Cf. A064442, A127549, A127550, A127551, A127552, A127553, A127555, A127556, A127557, A127558, A127559, A006562.
%K A127557 cons,nonn
%O A127557 1,1
%A A127557 _Artur Jasinski_, Jan 18 2007