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 A297783 #6 Jul 24 2023 11:41:39
%S A297783 1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,
%T A297783 2,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,
%U A297783 2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2
%N A297783 Number of distinct runs in base-15 digits of n.
%C A297783 Every positive integers occurs infinitely many times. See A297770 for a guide to related sequences.
%C A297783 Starts to differ from A043542 at n=3391. - _R. J. Mathar_, Jul 24 2023
%H A297783 Clark Kimberling, <a href="/A297783/b297783.txt">Table of n, a(n) for n = 1..10000</a>
%e A297783 12153600 in base-15: 1,1,0,1,1,0,0; four runs, of which 3 are distinct, so that a(12153600) = 3.
%t A297783 b = 15; s[n_] := Length[Union[Split[IntegerDigits[n, b]]]]
%t A297783 Table[s[n], {n, 1, 200}]
%Y A297783 Cf. A043567 (number of runs, not necessarily distinct), A297770.
%K A297783 nonn,base,easy
%O A297783 1,15
%A A297783 _Clark Kimberling_, Feb 03 2018