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A296764 Numbers n whose base-20 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments. 7
20, 40, 41, 60, 61, 62, 80, 81, 82, 83, 100, 101, 102, 103, 104, 120, 121, 122, 123, 124, 125, 140, 141, 142, 143, 144, 145, 146, 160, 161, 162, 163, 164, 165, 166, 167, 180, 181, 182, 183, 184, 185, 186, 187, 188, 200, 201, 202, 203, 204, 205, 206, 207, 208 (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 A296762-A296764 partition the natural numbers. See the guide at A296712.

LINKS

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

EXAMPLE

The base-20 digits of 208 are 10,8; here #(rises) = 0 and #(falls) = 2, so that 208 is in the sequence.

MATHEMATICA

z = 200; b = 20; d[n_] := Sign[Differences[IntegerDigits[n, b]]];

Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296762 *)

Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296763 *)

Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296764 *)

CROSSREFS

Cf. A296762, A296763, A296712.

Sequence in context: A040380 A154044 A235289 * A046794 A104153 A049057

Adjacent sequences:  A296761 A296762 A296763 * A296765 A296766 A296767

KEYWORD

nonn,base,easy

AUTHOR

Clark Kimberling, Jan 08 2018

STATUS

approved

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Last modified October 16 23:45 EDT 2019. Contains 328103 sequences. (Running on oeis4.)