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A296889 Numbers whose base-12 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments. 4
145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 433, 434, 435, 436, 437, 438, 439, 440, 441, 442, 443, 446, 447, 448, 449, 450, 451, 452, 453, 454 (list; graph; refs; listen; history; text; internal format)
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 A296888-A296890 partition the natural numbers. See the guides at A296712 and A296882.
LINKS
EXAMPLE
The base-12 digits of 43502 are 2,1,2,1,2; here #(pits) = 2 and #(peaks) = 1, so 43502 is in the sequence.
MATHEMATICA
z = 200; b = 12;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &] (* A296888 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &] (* A296889 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &] (* A296890 *)
CROSSREFS
Sequence in context: A126843 A099648 A043652 * A164770 A159777 A326258
KEYWORD
nonn,base,easy
AUTHOR
Clark Kimberling, Jan 10 2018
STATUS
approved

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Last modified June 23 04:59 EDT 2024. Contains 373629 sequences. (Running on oeis4.)