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 A297780 #4 Feb 04 2018 12:42:29
%S A297780 1,1,1,1,1,1,1,1,1,1,1,2,1,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2,
%T A297780 2,2,2,2,1,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,
%U A297780 2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2
%N A297780 Number of distinct runs in base-12 digits of n.
%C A297780 Every positive integers occurs infinitely many times. See A297770 for a guide to related sequences.
%H A297780 Clark Kimberling, <a href="/A297780/b297780.txt">Table of n, a(n) for n = 1..10000</a>
%e A297780 3006865 in base-12: 1,0,1,0,1,0,1; seven runs, of which 2 are distinct, so that a(3006865) = 2.
%t A297780 b = 12; s[n_] := Length[Union[Split[IntegerDigits[n, b]]]]
%t A297780 Table[s[n], {n, 1, 200}]
%Y A297780 Cf. A043564 (number of runs, not necessarily distinct), A297770.
%K A297780 nonn,base,easy
%O A297780 1,12
%A A297780 _Clark Kimberling_, Feb 03 2018