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A296756 Numbers whose base-15 digits d(m), d(m-1), ..., d(0) have #(rises) = #(falls); see Comments. 4

%I #7 Jan 27 2023 19:26:43

%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,16,32,48,64,80,96,112,128,144,160,

%T 176,192,208,224,226,227,228,229,230,231,232,233,234,235,236,237,238,

%U 239,241,255,256,270,271,272,285,286,287,288,300,301,302,303,304

%N Numbers whose base-15 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 A296756-A296758 partition the natural numbers. See the guide at A296712.

%H Clark Kimberling, <a href="/A296756/b296756.txt">Table of n, a(n) for n = 1..10000</a>

%e The base-15 digits of 2^20 are 1, 5, 10, 10, 5, 1; here #(rises) = 2 and #(falls) = 2, so 2^20 is in the sequence.

%t z = 200; b = 15; d[n_] := Sign[Differences[IntegerDigits[n, b]]];

%t Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296756 *)

%t Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &] (* A296757 *)

%t Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &] (* A296758 *)

%Y Cf. A296757, A296758, A296712.

%K nonn,base,easy

%O 1,2

%A _Clark Kimberling_, Jan 08 2018

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Last modified October 4 01:05 EDT 2023. Contains 365872 sequences. (Running on oeis4.)