A296893 Numbers whose base-13 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.

195, 196, 208, 209, 210, 221, 222, 223, 224, 234, 235, 236, 237, 238, 247, 248, 249, 250, 251, 252, 260, 261, 262, 263, 264, 265, 266, 273, 274, 275, 276, 277, 278, 279, 280, 286, 287, 288, 289, 290, 291, 292, 293, 294, 299, 300, 301, 302, 303, 304, 305, 306

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 A296891-A296894 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-13 digits of 33151 are 1,2,1,2,1; here #(pits) = 1 and #(peaks) = 2, so 33151 is in the sequence.

Mathematica

z = 200; b = 13;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296891 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296892 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296893 *)

Crossrefs

Cf. A296882, A296712, A296891, A296892.

Sequence in context: A220160 A333875 A183583 * A045073 A204811 A234814

Adjacent sequences: A296890 A296891 A296892 * A296894 A296895 A296896

Keyword

nonn,base,easy

Author

Clark Kimberling, Jan 12 2018

Status

approved