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 A303251 #4 Apr 20 2018 11:07:32 %S A303251 3,146,955,10264,106803,1105676,11394429,118856245,1230109648, %T A303251 12757693309,132384613354,1372891293534,14239793474152, %U A303251 147709542193598,1532064286940632,15891180965080859,164830841395830095 %N A303251 Number of nX5 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 A303251 Column 5 of A303254. %H A303251 R. H. Hardin, <a href="/A303251/b303251.txt">Table of n, a(n) for n = 1..210</a> %e A303251 Some solutions for n=5 %e A303251 ..0..1..0..0..0. .0..0..0..1..0. .0..0..1..0..1. .0..0..0..0..1 %e A303251 ..1..0..1..1..1. .1..1..1..0..1. .0..0..0..1..0. .0..0..1..1..1 %e A303251 ..1..1..1..0..0. .1..1..0..0..1. .0..1..0..1..1. .1..0..1..1..1 %e A303251 ..0..0..1..0..1. .1..0..1..1..1. .1..1..0..1..1. .1..1..0..0..1 %e A303251 ..0..0..1..1..0. .0..0..0..0..0. .1..0..0..0..1. .1..0..1..1..0 %Y A303251 Cf. A303254. %K A303251 nonn %O A303251 1,1 %A A303251 _R. H. Hardin_, Apr 20 2018