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 A023410 #14 Jan 27 2022 22:47:20 %S A023410 6,9,6,9,6,6,6,9,6,9,6,9,9,6,9,9,9,9,9,9,6,9,6,6,6,9,9,9,9,9,9,9,9,6, %T A023410 9,9,6,9,9,9,9,9,6,6,6,6,9,9,6,9,6,6,9,6,6,9,6,6,9,6,6,6,6,9,6,6,9,6, %U A023410 9,9,9,6,6,9,9,9,6,9,9,9,6,6,6,6,6,9,6,6,9,9,9,6,9,6,9,9,6,9,6,9,9,6,6,6,6,6,9,6 %N A023410 In base 10, if any power of 2 ends with k 6's and 9's, they must be the first k terms of this sequence in reverse order. %H A023410 Ray Chandler, <a href="/A023410/b023410.txt">Table of n, a(n) for n = 1..10000</a> %F A023410 a(n) = 3*A023397(n). %Y A023410 Cf. A023397. %K A023410 nonn,base %O A023410 1,1 %A A023410 _David W. Wilson_