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 A378719 #19 Mar 12 2025 05:43:06
%S A378719 19131872,20809344,20811488,21257636,22732948,172186880,1549681952,
%T A378719 2870345516,2870345520,2871907160,2872143356,2872251248,13947137600,
%U A378719 125524238432,496384984980,516044091344,530010360824,530030555544,530031618464,530032461188,530163415832,530260860088
%N A378719 Numbers k for which k/w = 3/4, where w is the number of numbers in the range {1..k} containing at least one decimal digit 1.
%H A378719 Karl-Heinz Hofmann and Hugo Pfoertner, <a href="/A378719/b378719.txt">Table of n, a(n) for n = 1..37</a>
%H A378719 IBM Research, <a href="https://research.ibm.com/haifa/ponderthis/challenges/December2024.html">Counting numbers with specific digits</a>, Ponder This Challenge December 2024, with a bonus question asking for the last term a(37) of this sequence.
%H A378719 Hugo Pfoertner, <a href="/A378719/a378719.txt">PARI program</a> (2025).
%H A378719 Karl-Heinz Hofmann, <a href="/A378719/a378719_1.txt">Python program</a>.
%H A378719 Karl-Heinz Hofmann, <a href="/A378719/a378719.gif">Graph zoom to a(8) and a(9)</a> (animated gif).
%H A378719 Karl-Heinz Hofmann, <a href="/A378719/a378719.png">Whole Graph up to a(37) (then diverging) </a>.
%o A378719 (PARI) \\ See link
%o A378719 (Python) # See link
%Y A378719 Cf. A004835, A346685.
%K A378719 nonn,base,fini,full
%O A378719 1,1
%A A378719 _Karl-Heinz Hofmann_ and _Hugo Pfoertner_, Dec 05 2024