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 A114911 #5 Oct 19 2017 03:15:00 %S A114911 7,777,8787,886845,7777777,878754321,8888787871,887885887811, %T A114911 8878878767816,878787878787878,8888888677748678,888888887867751312, %U A114911 8787878787873543211,888878888387777136788,8888888888486868617568 %N A114911 a(n) is the largest base-9 string such that the n-th number coprime to 9 does not divide any substring of a(n). %e A114911 a(3) = 777 (base 9) because the 3rd number coprime to 9 is 4, and 4 does not divide any substring of a(3). %K A114911 nonn,base %O A114911 2,1 %A A114911 _Don Reble_, Feb 20 2006