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 A043561 #9 Apr 23 2021 21:55:16
%S A043561 1,1,1,1,1,1,1,1,1,2,1,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2,2,1,2,2,2,
%T A043561 2,2,2,2,2,2,1,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,
%U A043561 2,2,1,2,2,2,2,2,2,2,2,2,1,2,3,3,3,3,3,3,3,3
%N A043561 Number of runs in base-9 representation of n.
%C A043561 Every positive integers occurs infinitely many times. See A297770 for a guide to related sequences.
%t A043561 b = 9; s[n_] := Length[Split[IntegerDigits[n, b]]];
%t A043561 Table[s[n], {n, 1, 200}]
%Y A043561 Cf. A297777 (number of distinct runs), A297770.
%K A043561 nonn,base
%O A043561 0,10
%A A043561 _Clark Kimberling_
%E A043561 Updated by _Clark Kimberling_, Feb 04 2018