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 A303256 #4 Apr 20 2018 11:11:08 %S A303256 0,111,1183,8664,106803,1218385,13529019,153269484,1719616546, %T A303256 19364602930,218131990331,2454766315292,27636145270965, %U A303256 311127611619222,3502509703999865,39430191355003478,443891694271539222 %N A303256 Number of 5Xn 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A303256 Row 5 of A303254. %H A303256 R. H. Hardin, <a href="/A303256/b303256.txt">Table of n, a(n) for n = 1..210</a> %e A303256 Some solutions for n=5 %e A303256 ..0..0..1..0..1. .0..1..1..1..0. .0..0..0..0..0. .0..0..1..1..0 %e A303256 ..0..1..1..1..0. .0..0..0..0..1. .0..1..1..0..1. .0..1..1..0..0 %e A303256 ..0..0..0..0..0. .1..1..1..0..1. .1..0..1..1..0. .0..1..0..0..1 %e A303256 ..1..0..1..1..1. .0..0..0..1..1. .0..0..0..1..0. .0..0..1..1..0 %e A303256 ..0..1..1..0..0. .0..0..1..1..1. .1..1..0..0..1. .0..1..0..0..1 %Y A303256 Cf. A303254. %K A303256 nonn %O A303256 1,2 %A A303256 _R. H. Hardin_, Apr 20 2018