|
%I #7 Jan 21 2023 18:04:41
%S 65,66,67,68,69,70,71,129,130,131,132,133,134,135,138,139,140,141,142,
%T 143,193,194,195,196,197,198,199,202,203,204,205,206,207,211,212,213,
%U 214,215,257,258,259,260,261,262,263,266,267,268,269,270,271,275,276
%N Numbers whose base-8 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments.
%C 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 Clark Kimberling, <a href="/A296877/b296877.txt">Table of n, a(n) for n = 1..10000</a>
%e The base-8 digits of 276 are 4,2,4; here #(pits) = 1 and #(peaks) = 0, so 276 is in the sequence.
%t z = 200; b = 8;
%t d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
%t Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &] (* A296876 *)
%t Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &] (* A296877 *)
%t Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &] (* A296878 *)
%Y Cf. A296882, A296712, A296876, A296878.
%K nonn,base,easy
%O 1,1
%A _Clark Kimberling_, Jan 09 2018
|
