A296699 Numbers whose base-5 digits d(m), d(m-1), ... d(0) have #(rises) < #(falls); see Comments.

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

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 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: A375320 A140507 A297255 * A297132 A136823 A275200

Adjacent sequences: A296696 A296697 A296698 * A296700 A296701 A296702

Keyword

nonn,base

Author

Clark Kimberling, Dec 21 2017

Status

approved