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 A181033 #5 Jun 02 2025 03:11:57 %S A181033 1,5,41,827,36787,3729091,851302029,439621976195,512615852515459, %T A181033 1350668111471923517,8039144604242883698707, %U A181033 108102244692016476122031505,3283958267007000189206675439393,225377046019121585326666765445484971 %N A181033 Number of nX(n+2) binary matrices with no initial bit string in any row or column divisible by 4. %C A181033 Superdiagonal 2 of A181031 %H A181033 R. H. Hardin, <a href="/A181033/b181033.txt">Table of n, a(n) for n=1..22</a> %e A181033 Some solutions for 4X6 %e A181033 ..1..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..1 %e A181033 ..1..0..1..0..1..0....1..0..1..0..1..0....1..0..1..0..1..0....1..0..1..0..1..0 %e A181033 ..1..1..0..1..0..1....1..1..0..1..0..1....1..1..0..1..0..1....1..1..0..1..0..1 %e A181033 ..1..0..1..0..1..0....1..0..1..0..1..1....1..0..1..1..1..0....1..0..1..1..1..1 %K A181033 nonn %O A181033 1,2 %A A181033 _R. H. Hardin_ Sep 30 2010