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A296895
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Numbers whose base-14 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments.
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4
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197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 393, 394, 395, 396, 397, 398, 399, 400, 401, 402, 403, 404, 405, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 589, 590, 591, 592, 593, 594, 595, 596, 597, 598, 599, 600, 601, 604
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OFFSET
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1,1
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COMMENTS
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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.
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LINKS
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EXAMPLE
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The base-14 digits of 79984 are 2,1,2,1,2; here #(pits) = 2 and #(peaks) = 1, so 79984 is in the sequence.
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MATHEMATICA
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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 *)
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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