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A296908 Numbers whose base-60 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.

%I A296908 #16 Jan 21 2023 03:00:00
%S A296908 3720,3721,3780,3781,3782,3840,3841,3842,3843,3900,3901,3902,3903,
%T A296908 3904,3960,3961,3962,3963,3964,3965,4020,4021,4022,4023,4024,4025,
%U A296908 4026,4080,4081,4082,4083,4084,4085,4086,4087,4140,4141,4142,4143,4144,4145,4146,4147
%N A296908 Numbers whose base-60 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.
%C A296908 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 A296906..A296908 partition the natural numbers. See the guides at A296712 and A296882.
%H A296908 Clark Kimberling, <a href="/A296908/b296908.txt">Table of n, a(n) for n = 1..10000</a>
%e A296908 The base-60 digits of 13395721 are 1,2,1,2,1; here #(pits) = 1 and #(peaks) = 2, so 13395721 is in the sequence.
%t A296908 z = 200; b = 60;
%t A296908 d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
%t A296908 Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296906 *)
%t A296908 Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296907 *)
%t A296908 Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296908 *)
%Y A296908 Cf. A296882, A296712, A296906, A296907.
%K A296908 nonn,base,easy
%O A296908 1,1
%A A296908 _Clark Kimberling_, Jan 12 2018