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 A296875 #7 Jan 21 2023 18:11:12 %S A296875 63,64,70,71,72,77,78,79,80,84,85,86,87,88,91,92,93,94,95,96,119,120, %T A296875 121,126,127,128,129,133,134,135,136,137,140,141,142,143,144,145,175, %U A296875 176,177,178,182,183,184,185,186,189,190,191,192,193,194,231,232,233 %N A296875 Numbers whose base-7 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments. %C A296875 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 A296873-A296875 partition the natural numbers. See the guides at A296882 and A296712. %H A296875 Clark Kimberling, <a href="/A296875/b296875.txt">Table of n, a(n) for n = 1..9999</a> %e A296875 The base-7 digits of 233 are 4,5,2; here #(pits) = 0 and #(peaks) = 1, so 233 is in the sequence. %t A296875 z = 200; b = 7; %t A296875 d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]]; %t A296875 Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &] (* A296873 *) %t A296875 Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &] (* A296874 *) %t A296875 Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &] (* A296875 *) %Y A296875 Cf. A296882, A296712, A296873, A296874. %K A296875 nonn,base,easy %O A296875 1,1 %A A296875 _Clark Kimberling_, Jan 09 2018