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A296714
Numbers whose base-10 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments.
3
10, 20, 21, 30, 31, 32, 40, 41, 42, 43, 50, 51, 52, 53, 54, 60, 61, 62, 63, 64, 65, 70, 71, 72, 73, 74, 75, 76, 80, 81, 82, 83, 84, 85, 86, 87, 90, 91, 92, 93, 94, 95, 96, 97, 98, 100, 110, 200, 210, 211, 220, 221, 300, 310, 311, 320, 321, 322, 330, 331, 332
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 A296712-A296714 partition the natural numbers. See the guide at A296712.
LINKS
EXAMPLE
The base-10 digits of 332 are 3,3,2; here #(rises) = 0 and #(falls) = 1, so 332 is in the sequence.
MATHEMATICA
z = 200; b = 10; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296712 *)
Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &] (* A296713 *)
Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &] (* A296714 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Clark Kimberling, Jan 08 2018
STATUS
approved