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 A116278 #2 Mar 30 2012 17:40:40 %S A116278 7040,487249777145,512750222847,684330069116 %N A116278 n times n+9 gives the concatenation of two numbers m and m-2. %e A116278 7040 * 7049 = 4962//4960, where // denotes concatenation. %Y A116278 Cf. A116147, A116271, A116277, A116284. %K A116278 nonn,base %O A116278 1,1 %A A116278 _Giovanni Resta_, Feb 06 2006