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A297240 Down-variation of the base-14 digits of n; see Comments.

%I A297240 #7 Jan 19 2018 16:22:06
%S A297240 0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,2,1,0,0,0,0,0,
%T A297240 0,0,0,0,0,0,0,3,2,1,0,0,0,0,0,0,0,0,0,0,0,4,3,2,1,0,0,0,0,0,0,0,0,0,
%U A297240 0,5,4,3,2,1,0,0,0,0,0,0,0,0,0,6,5,4
%N A297240 Down-variation of the base-14 digits of n; see Comments.
%C A297240 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). Every positive integer occurs infinitely many times. See A297330 for a guide to related sequences and partitions of the natural numbers.
%H A297240 Clark Kimberling, <a href="/A297240/b297240.txt">Table of n, a(n) for n = 1..10000</a>
%e A297240 28 in base 14: 2,0; here DV = 2, so that a(28) = 2.
%t A297240 g[n_, b_] := Differences[IntegerDigits[n, b]];
%t A297240 b = 14; z = 120; Table[-Total[Select[g[n, b], # < 0 &]], {n, 1, z}];  (* A297240 *)
%t A297240 Table[Total[Select[g[n, b], # > 0 &]], {n, 1, z}]; (* A297241 *)
%Y A297240 Cf. A297241, A297242, A297330.
%K A297240 nonn,base,easy
%O A297240 1,28
%A A297240 _Clark Kimberling_, Jan 17 2018