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A296883 Numbers n whose base-10 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments. 3
101, 102, 103, 104, 105, 106, 107, 108, 109, 201, 202, 203, 204, 205, 206, 207, 208, 209, 212, 213, 214, 215, 216, 217, 218, 219, 301, 302, 303, 304, 305, 306, 307, 308, 309, 312, 313, 314, 315, 316, 317, 318, 319, 323, 324, 325, 326, 327, 328, 329, 401, 402 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A pit is an index i such that d(i-1) > d(i) < d(i+1); a peak is an index i such that d(i-1) < d(i) > d(i+1). The sequences A296882-A296883 partition the natural numbers. See the guides at A296712 and A296882.

LINKS

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

EXAMPLE

The base-10 digits of 21212 are 2,1,2,1,2; here #(pits) = 2 and #(peaks) = 1, so that 21212 is in the sequence.

MATHEMATICA

z = 200; b = 10;

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

Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296882 *)

Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296883 *)

Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296884 *)

CROSSREFS

Cf. A296882, A296712, A296882, A296884.

Sequence in context: A138719 A043639 A152054 * A183086 A134808 A274612

Adjacent sequences:  A296880 A296881 A296882 * A296884 A296885 A296886

KEYWORD

nonn,base,easy

AUTHOR

Clark Kimberling, Jan 10 2018

STATUS

approved

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Last modified July 30 17:21 EDT 2021. Contains 346359 sequences. (Running on oeis4.)