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A296703 Numbers n whose base-7 digits d(m), d(m-1), ... d(0) have #(rises) = #(falls); see Comments. 4
1, 2, 3, 4, 5, 6, 8, 16, 24, 32, 40, 48, 50, 51, 52, 53, 54, 55, 57, 63, 64, 70, 71, 72, 77, 78, 79, 80, 84, 85, 86, 87, 88, 91, 92, 93, 94, 95, 96, 99, 100, 101, 102, 103, 104, 107, 108, 109, 110, 111, 114, 119, 120, 121, 126, 127, 128, 129, 133, 134, 135 (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 A296703-A296705 partition the natural numbers. See the guide at A296712.

LINKS

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

EXAMPLE

The base-7 digits of 135 are 2,5,2; here #(rises) = 1 and #(falls) = 1, so that 135 is in the sequence.

MATHEMATICA

z = 200; b = 7; d[n_] := Sign[Differences[IntegerDigits[n, b]]];

Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296703 *)

Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296704 *)

Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296705 *)

CROSSREFS

Cf. A296704, A296705, A296712.

Sequence in context: A297139 A048304 A043710 * A297262 A029954 A048318

Adjacent sequences:  A296700 A296701 A296702 * A296704 A296705 A296706

KEYWORD

nonn,easy,base

AUTHOR

Clark Kimberling, Jan 07 2018

STATUS

approved

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Last modified November 15 01:06 EST 2019. Contains 329142 sequences. (Running on oeis4.)