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 A301903 #4 Mar 28 2018 16:07:12 %S A301903 1,3,2,8,12,64,196,864,3236,13280,52260,210400,838180,3358176, %T A301903 13419044,53698016,214737444,859037152,3435930148,13744070112, %U A301903 54975406628,219903024608,879608603172,3518440005088,14073746039332,56295006526944 %N A301903 Number of nX5 0..1 arrays with every element equal to 0, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero. %C A301903 Column 5 of A301906. %H A301903 R. H. Hardin, <a href="/A301903/b301903.txt">Table of n, a(n) for n = 1..210</a> %F A301903 Empirical: a(n) = 4*a(n-1) +5*a(n-2) -20*a(n-3) -4*a(n-4) +16*a(n-5) for n>6 %e A301903 Some solutions for n=5 %e A301903 ..0..1..1..1..1. .0..1..1..0..0. .0..1..0..1..0. .0..1..1..0..0 %e A301903 ..1..1..0..1..1. .1..1..0..0..0. .0..1..0..1..0. .1..1..0..0..1 %e A301903 ..1..1..0..1..1. .0..1..1..0..1. .0..1..0..1..0. .0..1..0..0..0 %e A301903 ..1..1..0..1..1. .1..1..0..0..0. .0..1..0..1..0. .0..1..1..0..0 %e A301903 ..1..1..1..1..0. .0..1..0..0..1. .0..1..0..1..0. .1..1..0..0..1 %Y A301903 Cf. A301906. %K A301903 nonn %O A301903 1,2 %A A301903 _R. H. Hardin_, Mar 28 2018