cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A296872 Numbers whose base-6 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.

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%I A296872 #11 Jan 22 2023 18:58:45
%S A296872 48,49,54,55,56,60,61,62,63,66,67,68,69,70,90,91,92,96,97,98,99,102,
%T A296872 103,104,105,106,132,133,134,135,138,139,140,141,142,174,175,176,177,
%U A296872 178,264,265,270,271,272,276,277,278,279,282,283,284,285,286,288,294
%N A296872 Numbers whose base-6 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.
%C A296872 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 A296870-A296872 partition the natural numbers. See the guides at A296882 and A296712.
%H A296872 Clark Kimberling, <a href="/A296872/b296872.txt">Table of n, a(n) for n = 1..10000</a>
%e A296872 The base-6 digits of 294 are 1,2,1,0; here #(pits) = 0 and #(peaks) = 1, so 294 is in the sequence.
%t A296872 z = 200; b = 6;
%t A296872 d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
%t A296872 Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296870 *)
%t A296872 Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296871 *)
%t A296872 Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296872 *)
%Y A296872 Cf. A296882, A296712, A296870, A296871.
%K A296872 nonn,base,easy
%O A296872 1,1
%A A296872 _Clark Kimberling_, Jan 09 2018