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A296753
Numbers whose base-14 digits d(m), d(m-1), ..., d(0) have #(rises) = #(falls); see Comments.
6
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 211, 224, 225, 238, 239, 240, 252, 253, 254, 255, 266, 267, 268, 269, 270, 280, 281, 282
OFFSET
1,2
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 A296753-A296755 partition the natural numbers. See the guide at A296712.
LINKS
EXAMPLE
The base-14 digits of 1000000 are 2,8,6,2,12; here #(rises) = 2 and #(falls) = 2, so 1000000 is in the sequence.
MATHEMATICA
z = 200; b = 14; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296753 *)
Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &] (* A296754 *)
Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &] (* A296755 *)
Select[Range[300], Total[Sign[Differences[IntegerDigits[#, 14]]]]==0&] (* Harvey P. Dale, Sep 20 2022 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Clark Kimberling, Jan 08 2018
STATUS
approved