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 A116243 #2 Mar 30 2012 17:40:40 %S A116243 38,56,32262230,67737764,79321054,3341093417798787499091, %T A116243 3861488851737861033959,4747922651210186579785,5252077348789813420209, %U A116243 6138511148262138966035,6658906582201212500903,7232275368591793618229 %N A116243 n times n+7 gives the concatenation of two numbers m and m-7. %e A116243 79321054 * 79321061 = 62918301//62918294, where // denotes %e A116243 concatenation. %Y A116243 Cf. A116112, A116238, A116242, A116244, A116250. %K A116243 nonn,base %O A116243 1,1 %A A116243 _Giovanni Resta_, Feb 06 2006