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 A302736 #4 Apr 12 2018 11:18:04 %S A302736 4,32,228,1652,11980,86916,630604,4575332,33196332,240856196, %T A302736 1747533964,12679246500,91994373868,667465912772,4842804251724, %U A302736 35137004861924,254936818941100,1849696122577668,13420484966010892,97372435679847716 %N A302736 Number of nX3 0..1 arrays with every element equal to 0, 1, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302736 Column 3 of A302741. %H A302736 R. H. Hardin, <a href="/A302736/b302736.txt">Table of n, a(n) for n = 1..210</a> %F A302736 Empirical: a(n) = 7*a(n-1) +2*a(n-2) +2*a(n-3) -20*a(n-4) -16*a(n-5) %e A302736 Some solutions for n=5 %e A302736 ..0..0..1. .0..0..0. .0..1..0. .0..0..0. .0..1..0. .0..0..1. .0..1..0 %e A302736 ..0..0..0. .0..1..0. .0..1..1. .0..0..1. .1..1..0. .1..1..1. .1..0..0 %e A302736 ..1..0..1. .1..1..0. .0..1..0. .0..1..1. .0..0..0. .0..1..1. .1..1..0 %e A302736 ..1..0..0. .0..1..0. .1..1..0. .1..0..1. .1..0..1. .0..1..1. .0..1..0 %e A302736 ..1..0..0. .1..0..1. .1..0..1. .0..0..0. .1..0..0. .0..0..0. .0..1..1 %Y A302736 Cf. A302741. %K A302736 nonn %O A302736 1,1 %A A302736 _R. H. Hardin_, Apr 12 2018