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 A296866 Numbers whose base-4 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments. 4
 24, 25, 28, 29, 30, 44, 45, 46, 88, 89, 92, 93, 94, 96, 100, 101, 108, 109, 110, 112, 116, 117, 120, 121, 122, 172, 173, 174, 176, 180, 181, 184, 185, 186, 260, 264, 265, 268, 269, 270, 344, 345, 348, 349, 350, 352, 356, 357, 364, 365, 366, 368, 372, 373 (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 A296864-A296866 partition the natural numbers. See the guides at A296882 and A296712. LINKS Clark Kimberling, Table of n, a(n) for n = 1..9999 EXAMPLE The base-4 digits of 373 are 1,1,3,1,1; here #(pits) = 0 and #(peaks) = 2, so 373 is in the sequence. MATHEMATICA z = 200; b = 4; d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]]; Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &] (* A296864 *) Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &] (* A296865 *) Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &] (* A296866 *) CROSSREFS Cf. A296882, A296712, A296864, A296865. Sequence in context: A066024 A123608 A141587 * A241890 A027729 A008856 Adjacent sequences: A296863 A296864 A296865 * A296867 A296868 A296869 KEYWORD nonn,base,easy AUTHOR Clark Kimberling, Jan 09 2018 STATUS approved

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Last modified May 28 01:34 EDT 2024. Contains 372900 sequences. (Running on oeis4.)