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 A114879 #8 Dec 01 2018 08:01:19 %S A114879 2,4,5,10,20,37 %N A114879 Numbers n coprime to 3 such that there exists an (n-1)-digit ternary number wherein each substring is indivisible by n. %C A114879 a(7) > 64. %e A114879 20 is there because each substring of 1121212211122121211 (base 3) is indivisible by 20. %Y A114879 Cf. A114880, A114942, A114943, A114944, A114908, A114909, A114910, A114911, A114922. %K A114879 nonn,base,more,hard %O A114879 1,1 %A A114879 _Don Reble_, Feb 17 2006