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 A031242 #15 Jul 23 2025 05:35:59 %S A031242 1,1,1,1,1,2,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,2,1, %T A031242 1,1,1,1,1,1,1,3,2,2,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, %U A031242 1,1,2,1,1,1,1,1,1,1,1,2,1,1,1,1,1 %N A031242 Length of n-th run of digit 0 in A031235. %C A031242 Differs from A031226 whenever a base 5 sequence of a number is inserted which has a non-palindromic sequence of run-lengths of 0. Happens first scanning 10010_5 = 630_10 which is inserted in A031235 as 01001 (run lengths 1,2) but in A031219 as 10010 (run lengths 2,1). - _R. J. Mathar_, Jul 23 2025 %K A031242 nonn,base %O A031242 1,6 %A A031242 _Clark Kimberling_ %E A031242 a(1)=1 inserted for consistency with change in A031235 by _Sean A. Irvine_, Apr 19 2020