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A296696 Numbers n whose base-4 digits d(m), d(m-1), ... d(0) have #(rises) < #(falls); see Comments. 4
4, 8, 9, 12, 13, 14, 16, 20, 32, 36, 37, 40, 41, 48, 52, 53, 56, 57, 58, 60, 61, 62, 64, 68, 72, 73, 76, 77, 78, 80, 84, 100, 116, 120, 121, 128, 132, 136, 137, 140, 141, 142, 144, 145, 146, 147, 148, 149, 152, 153, 156, 157, 158, 160, 164, 165, 168, 169 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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 A296694-A296696 partition the natural numbers. See the guide at A296712.

LINKS

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

EXAMPLE

The base-4 digits of 196 are 3,0,1,0; here #(rises) = 1 and #(falls) = 2, so that 196 is in the sequence.

MATHEMATICA

z = 200; b = 4; d[n_] := Sign[Differences[IntegerDigits[n, b]]];

Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296694 *)

Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296695 *)

Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296696 *)

CROSSREFS

Cf. A296694, A296695, A296712.

Sequence in context: A306976 A266142 A297252 * A297129 A078137 A294574

Adjacent sequences:  A296693 A296694 A296695 * A296697 A296698 A296699

KEYWORD

nonn,base

AUTHOR

Clark Kimberling, Dec 21 2017

EXTENSIONS

Example corrected by Harvey P. Dale, Sep 04 2018

STATUS

approved

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Last modified September 17 09:11 EDT 2019. Contains 327128 sequences. (Running on oeis4.)