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A296756 Numbers n whose base-15 digits d(m), d(m-1), ..., d(0) have #(rises) = #(falls); see Comments. 4
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 241, 255, 256, 270, 271, 272, 285, 286, 287, 288, 300, 301, 302, 303, 304 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..10000

EXAMPLE

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

MATHEMATICA

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

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

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

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

CROSSREFS

Cf. A296757, A296758, A296712.

Sequence in context: A044826 A048312 A043718 * A029960 A297286 A048326

Adjacent sequences:  A296753 A296754 A296755 * A296757 A296758 A296759

KEYWORD

nonn,base,easy

AUTHOR

Clark Kimberling, Jan 08 2018

STATUS

approved

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Last modified November 12 09:29 EST 2019. Contains 329054 sequences. (Running on oeis4.)