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 A116237 #2 Mar 30 2012 17:40:40 %S A116237 7,9,97,99,425,570,724,843,997,999,7807,9997,9999,36362,63633,99997, %T A116237 99999,326731,673264,999997,999999,4545451,5454544,9999997,9999999, %U A116237 47058820,52941175,99999997,99999999,331983804,332667331,384615383 %N A116237 n times n+6 gives the concatenation of two numbers m and m-8. %Y A116237 Cf. A116106, A116229, A116236, A116238, A116242. %K A116237 nonn,base %O A116237 1,1 %A A116237 _Giovanni Resta_, Feb 06 2006