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 A066774 #5 Mar 30 2012 18:38:46 %S A066774 4,13,15,19,21,27,31,35,37,39,51,53,57,65,67,69,77,83,87,89,95,109, %T A066774 111,113,125,127,129,131,139,155,157,161,177,181,199,209,211,221,233, %U A066774 237,249,251,257,263,267,291,293,305,307,309,317,329,335,337,353,365,371 %N A066774 A066728(a(n))=3. %C A066774 Conjecture: the set of k such that a(k+1)-a(k)=2 is infinite. %F A066774 If a(k+1)-a(k)=2 then a(k) or a(k+1) is prime. For example : a(9)-a(8)=37-35 and a(9)=37 is prime. a(16)-a(15)=69-67=2 and a(15)=67 is prime. %Y A066774 Cf. A066728. %K A066774 nonn %O A066774 1,1 %A A066774 _Benoit Cloitre_, Jan 16 2002