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.
%I A296866 #7 Jan 22 2023 20:51:02 %S A296866 24,25,28,29,30,44,45,46,88,89,92,93,94,96,100,101,108,109,110,112, %T A296866 116,117,120,121,122,172,173,174,176,180,181,184,185,186,260,264,265, %U A296866 268,269,270,344,345,348,349,350,352,356,357,364,365,366,368,372,373 %N A296866 Numbers whose base-4 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments. %C A296866 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 A296864-A296866 partition the natural numbers. See the guides at A296882 and A296712. %H A296866 Clark Kimberling, <a href="/A296866/b296866.txt">Table of n, a(n) for n = 1..9999</a> %e A296866 The base-4 digits of 373 are 1,1,3,1,1; here #(pits) = 0 and #(peaks) = 2, so 373 is in the sequence. %t A296866 z = 200; b = 4; %t A296866 d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]]; %t A296866 Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &] (* A296864 *) %t A296866 Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &] (* A296865 *) %t A296866 Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &] (* A296866 *) %Y A296866 Cf. A296882, A296712, A296864, A296865. %K A296866 nonn,base,easy %O A296866 1,1 %A A296866 _Clark Kimberling_, Jan 09 2018