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 A053376 #7 Jun 13 2020 15:10:40
%S A053376 8,88,888,1888,81888,181888,8181888,18181888,118181888,8118181888,
%T A053376 88118181888,888118181888,8888118181888,88888118181888,
%U A053376 888888118181888,1888888118181888,81888888118181888,181888888118181888
%N A053376 a(n) contains n digits (either '1' or '8') and is divisible by 2^n.
%H A053376 Ray Chandler, <a href="/A053376/b053376.txt">Table of n, a(n) for n = 1..1000</a>
%F A053376 a(n)=a(n-1)+10^(n-1)*(8-7*[a(n-1)/2^(n-1) mod 2]) i.e. a(n) ends with a(n-1); if (n-1)-th term is divisible by 2^n then n-th term begins with an 8, if not then n-th term begins with a 1.
%t A053376 Table[Select[FromDigits/@Tuples[{1,8},n],Divisible[#,2^n]&],{n,20}]// Flatten (* _Harvey P. Dale_, Aug 20 2017 *)
%Y A053376 Cf. A023411, A050621, A050622, A035014.
%K A053376 base,nonn
%O A053376 1,1
%A A053376 _Henry Bottomley_, Mar 06 2000