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A296694 Numbers n whose base-4 digits d(m), d(m-1), ... d(0) have #(rises) = #(falls); see Comments. 4
1, 2, 3, 5, 10, 15, 17, 18, 19, 21, 24, 25, 28, 29, 30, 33, 34, 35, 38, 39, 42, 44, 45, 46, 49, 50, 51, 54, 55, 59, 63, 65, 66, 67, 69, 74, 79, 81, 82, 83, 85, 88, 89, 92, 93, 94, 96, 101, 104, 105, 112, 117, 122, 124, 125, 126, 129, 130, 131, 133, 138, 143 (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 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 143 are 2,0,3,3; here #(rises) = 1 and #(falls) = 1, so that 143 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. A296695, A296696, A296700, A296712.

Sequence in context: A044815 A048301 A043707 * A297253 A014192 A250746

Adjacent sequences:  A296691 A296692 A296693 * A296695 A296696 A296697

KEYWORD

nonn,base

AUTHOR

Clark Kimberling, Dec 21 2017

STATUS

approved

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Last modified October 18 16:14 EDT 2018. Contains 316323 sequences. (Running on oeis4.)