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A296699 Numbers n whose base-5 digits d(m), d(m-1), ... d(0) have #(rises) < #(falls); see Comments. 4

%I

%S 5,10,11,15,16,17,20,21,22,23,25,30,50,55,56,60,61,75,80,81,85,86,87,

%T 90,91,92,100,105,106,110,111,112,115,116,117,118,120,121,122,123,125,

%U 130,135,136,140,141,142,145,146,147,148,150,155,180,205,210,211

%N Numbers n whose base-5 digits d(m), d(m-1), ... d(0) have #(rises) < #(falls); see Comments.

%C A rise is an index i such that d(i) < d(i+1); a fall is an index i such that d(i) > d(i+1). The sequences A296697-A296699 partition the natural numbers. See the guide at A296712.

%H Clark Kimberling, <a href="/A296699/b296699.txt">Table of n, a(n) for n = 1..10000</a>

%e The base-5 digits of 211 are 1,3,2,1; here #(rises) = 1 and #(falls) = 2, so that 211 is in the sequence.

%t z = 200; b = 5; d[n_] := Sign[Differences[IntegerDigits[n, b]]];

%t Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296697 *)

%t Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &] (* A296698 *)

%t Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &] (* A296699 *)

%Y Cf. A296697, A296698, A296712.

%K nonn,base

%O 1,1

%A _Clark Kimberling_, Dec 21 2017

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Last modified October 25 01:40 EDT 2021. Contains 348233 sequences. (Running on oeis4.)