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 A123272 #4 Mar 30 2012 18:40:03 %S A123272 1,1,1,0,0,1,1,0,0,0,1,0,1,0,1,1,1,1,0,0,0,0,0,1,0,0,0,0,1,0,0,1,1,0, %T A123272 0,0,0,0,0,0,1,0,0,1,1,0,0,0,1,0,0,0,1,0,1,0,0,0,0,0,1,0,1,1,0,1,1,0, %U A123272 0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,1,1,0,0,0 %N A123272 Number of primes between consecutive terms of A105575. %F A123272 a(n) = PrimePi(A105575(n+1)) - PrimePi(A105575(n)) - 1. %Y A123272 Cf. A105575. %K A123272 easy,nonn %O A123272 1,1 %A A123272 _Giovanni Teofilatto_, Oct 10 2006 %E A123272 Edited and extended by _Ray Chandler_, Oct 17 2006