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A296699 Numbers n whose base-5 digits d(m), d(m-1), ... d(0) have #(rises) < #(falls); see Comments. 4
5, 10, 11, 15, 16, 17, 20, 21, 22, 23, 25, 30, 50, 55, 56, 60, 61, 75, 80, 81, 85, 86, 87, 90, 91, 92, 100, 105, 106, 110, 111, 112, 115, 116, 117, 118, 120, 121, 122, 123, 125, 130, 135, 136, 140, 141, 142, 145, 146, 147, 148, 150, 155, 180, 205, 210, 211 (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 A296697-A296699 partition the natural numbers. See the guide at A296712.

LINKS

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

EXAMPLE

The base-5 digits of 211 are 1,3,2,1; here #(rises) = 1 and #(falls) = 2, so that 211 is in the sequence.

MATHEMATICA

z = 200; b = 5; d[n_] := Sign[Differences[IntegerDigits[n, b]]];

Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296697 *)

Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296698 *)

Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296699 *)

CROSSREFS

Cf. A296697, A296698, A296712.

Sequence in context: A290469 A140507 A297255 * A297132 A136823 A275200

Adjacent sequences:  A296696 A296697 A296698 * A296700 A296701 A296702

KEYWORD

nonn,base

AUTHOR

Clark Kimberling, Dec 21 2017

STATUS

approved

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Last modified December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)