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A296752 Numbers n whose base-13 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments. 5
13, 26, 27, 39, 40, 41, 52, 53, 54, 55, 65, 66, 67, 68, 69, 78, 79, 80, 81, 82, 83, 91, 92, 93, 94, 95, 96, 97, 104, 105, 106, 107, 108, 109, 110, 111, 117, 118, 119, 120, 121, 122, 123, 124, 125, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 143, 144 (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 A296751-A296753 partition the natural numbers. See the guide at A296712.

LINKS

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

EXAMPLE

The base-13 digits of 914 are 5,5,4; here #(rises) = 0 and #(falls) = 1, so that 914 is in the sequence.

MATHEMATICA

z = 200; b = 13; d[n_] := Sign[Differences[IntegerDigits[n, b]]];

Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296750 *)

Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296751 *)

Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296752 *)

CROSSREFS

Cf. A296750, A296751, A296712.

Sequence in context: A226051 A238338 A040156 * A297279 A095781 A037974

Adjacent sequences:  A296749 A296750 A296751 * A296753 A296754 A296755

KEYWORD

nonn,base,easy

AUTHOR

Clark Kimberling, Jan 08 2018

STATUS

approved

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Last modified November 12 04:21 EST 2019. Contains 329051 sequences. (Running on oeis4.)