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A297285 Numbers whose base-15 digits have greater down-variation than up-variation; see Comments.

%I A297285 #8 Jan 23 2018 20:16:43
%S A297285 15,30,31,45,46,47,60,61,62,63,75,76,77,78,79,90,91,92,93,94,95,105,
%T A297285 106,107,108,109,110,111,120,121,122,123,124,125,126,127,135,136,137,
%U A297285 138,139,140,141,142,143,150,151,152,153,154,155,156,157,158,159,165
%N A297285 Numbers whose base-15 digits have greater down-variation than up-variation; see Comments.
%C A297285 Suppose that 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 the guide at A297330.
%C A297285 Differs from A296758 first for 255 = 120_15, which has the same number of rises and falls and is not in A296758, but DV(255,15) =2 > UV(255,15) =1 and is in this sequence. - _R. J. Mathar_, Jan 23 2018
%H A297285 Clark Kimberling, <a href="/A297285/b297285.txt">Table of n, a(n) for n = 1..10000</a>
%e A297285 165 in base-15:  11,0 having DV = 11, UV = 0, so that 165 is in the sequence.
%t A297285 g[n_, b_] := Map[Total, GatherBy[Differences[IntegerDigits[n, b]], Sign]];
%t A297285 x[n_, b_] := Select[g[n, b], # < 0 &]; y[n_, b_] := Select[g[n, b], # > 0 &];
%t A297285 b = 15; z = 2000; p = Table[x[n, b], {n, 1, z}]; q = Table[y[n, b], {n, 1, z}];
%t A297285 w = Sign[Flatten[p /. {} -> {0}] + Flatten[q /. {} -> {0}]];
%t A297285 Take[Flatten[Position[w, -1]], 120]   (* A297285 *)
%t A297285 Take[Flatten[Position[w, 0]], 120]    (* A297286 *)
%t A297285 Take[Flatten[Position[w, 1]], 120]    (* A297287 *)
%Y A297285 Cf. A297330, A297286, A297287.
%K A297285 nonn,base,easy
%O A297285 1,1
%A A297285 _Clark Kimberling_, Jan 17 2018