A296871 Numbers whose base-6 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments.

37, 38, 39, 40, 41, 73, 74, 75, 76, 77, 80, 81, 82, 83, 109, 110, 111, 112, 113, 116, 117, 118, 119, 123, 124, 125, 145, 146, 147, 148, 149, 152, 153, 154, 155, 159, 160, 161, 166, 167, 181, 182, 183, 184, 185, 188, 189, 190, 191, 195, 196, 197, 202, 203

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 A296870-A296872 partition the natural numbers. See the guides at A296882 and A296712.

Links

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

Example

The base-6 digits of 203 are 5,3,5; here #(pits) = 1 and #(peaks) = 0, so 203 is in the sequence.

Mathematica

z = 200; b = 6;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296870 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296871 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296872 *)

Crossrefs

Cf. A296882, A296712, A296870, A296872.

Sequence in context: A190839 A185698 A043611 * A346383 A337453 A071887

Adjacent sequences: A296868 A296869 A296870 * A296872 A296873 A296874

Keyword

nonn,base,easy

Author

Clark Kimberling, Jan 09 2018

Status

approved