

A296705


Numbers n whose base7 digits d(m), d(m1), ..., d(0) have #(rises) < #(falls); see Comments.


4



7, 14, 15, 21, 22, 23, 28, 29, 30, 31, 35, 36, 37, 38, 39, 42, 43, 44, 45, 46, 47, 49, 56, 98, 105, 106, 112, 113, 147, 154, 155, 161, 162, 163, 168, 169, 170, 196, 203, 204, 210, 211, 212, 217, 218, 219, 220, 224, 225, 226, 227, 245, 252, 253, 259, 260, 261
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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 A296703A296705 partition the natural numbers. See the guide at A296712.


LINKS

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


EXAMPLE

The base7 digits of 261 are 5,2,2; here #(rises) = 0 and #(falls) = 2, so that 261 is in the sequence.


MATHEMATICA

z = 200; b = 7; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
Select[Range [z], Count[d[#], 1] == Count[d[#], 1] &] (* A296703 *)
Select[Range [z], Count[d[#], 1] < Count[d[#], 1] &] (* A296704 *)
Select[Range [z], Count[d[#], 1] > Count[d[#], 1] &] (* A296705 *)


CROSSREFS

Cf. A296703, A296704, A296712.
Sequence in context: A022557 A307546 A297261 * A297138 A085335 A069137
Adjacent sequences: A296702 A296703 A296704 * A296706 A296707 A296708


KEYWORD

nonn,easy,base


AUTHOR

Clark Kimberling, Jan 08 2018


STATUS

approved



