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 A297233 #4 Jan 17 2018 14:24:02
%S A297233 0,0,0,0,0,0,0,0,0,0,1,0,1,2,3,4,5,6,7,8,9,2,1,0,1,2,3,4,5,6,7,8,3,2,
%T A297233 1,0,1,2,3,4,5,6,7,4,3,2,1,0,1,2,3,4,5,6,5,4,3,2,1,0,1,2,3,4,5,6,5,4,
%U A297233 3,2,1,0,1,2,3,4,7,6,5,4,3,2,1,0,1,2
%N A297233 Total variation of base-11 digits of n; see Comments.
%C A297233 Suppose that a number n has base-b digits b(m), b(m-1), ..., b(0). The base-b down-variation of n is the sum DV(n,b) of all d(i)-d(i-1) for which d(i) > d(i-1); the base-b up-variation of n is the sum UV(n,b) of all d(k-1)-d(k) for which d(k) < d(k-1). The total base-b variation of n is the sum TV(n,b) = DV(n,b) + UV(n,b). See A297330 for a guide to related sequences and partitions of the natural numbers:
%H A297233 Clark Kimberling, <a href="/A297233/b297233.txt">Table of n, a(n) for n = 1..10000</a>
%e A297233 2^20 in base 11: 6, 5, 6, 8, 10, 1; here, DV = 12 and UV = 5, so that a(2^20) = 17.
%t A297233 b = 11; z = 120; t = Table[Total@Flatten@Map[Abs@Differences@# &, Partition[IntegerDigits[n, b], 2, 1]], {n, z}] (* cf. Michael De Vlieger, e.g. A037834 *)
%Y A297233 Cf. A297231, A297232, A297330.
%K A297233 nonn,base,easy
%O A297233 1,14
%A A297233 _Clark Kimberling_, Jan 17 2018