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A296896
Numbers whose base-14 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.
4
224, 225, 238, 239, 240, 252, 253, 254, 255, 266, 267, 268, 269, 270, 280, 281, 282, 283, 284, 285, 294, 295, 296, 297, 298, 299, 300, 308, 309, 310, 311, 312, 313, 314, 315, 322, 323, 324, 325, 326, 327, 328, 329, 330, 336, 337, 338, 339, 340, 341, 342, 343
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 A296894-A296896 partition the natural numbers. See the guides at A296712 and A296882.
LINKS
EXAMPLE
The base-14 digits of 44129 are 1,2,1,2,1; here #(pits) = 1 and #(peaks) = 2, so 44129 is in the sequence.
MATHEMATICA
z = 200; b = 14;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &] (* A296894 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &] (* A296895 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &] (* A296896 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Clark Kimberling, Jan 12 2018
STATUS
approved