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A296878 Numbers whose base-8 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.

%I A296878 #7 Jan 21 2023 18:06:25
%S A296878 80,81,88,89,90,96,97,98,99,104,105,106,107,108,112,113,114,115,116,
%T A296878 117,120,121,122,123,124,125,126,152,153,154,160,161,162,163,168,169,
%U A296878 170,171,172,176,177,178,179,180,181,184,185,186,187,188,189,190,224
%N A296878 Numbers whose base-8 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.
%C A296878 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 A296876-A296878 partition the natural numbers. See the guides at A296882 and A296712.
%H A296878 Clark Kimberling, <a href="/A296878/b296878.txt">Table of n, a(n) for n = 1..10000</a>
%e A296878 The base-8 digits of 224 are 3,4,0; here #(pits) = 0 and #(peaks) = 1, so 224 is in the sequence.
%t A296878 z = 200; b = 8;
%t A296878 d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
%t A296878 Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296876 *)
%t A296878 Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296877 *)
%t A296878 Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296878 *)
%Y A296878 Cf. A296882, A296712, A296876, A296877.
%K A296878 nonn,base,easy
%O A296878 1,1
%A A296878 _Clark Kimberling_, Jan 09 2018