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 A302228 #4 Apr 03 2018 12:19:28 %S A302228 0,111,675,4237,40395,338204,3018243,26373655,229022022,2020776808, %T A302228 17623530150,154526692002,1354126269239,11852307962264, %U A302228 103884063578946,909810907872807,7970268921853663,69825955304629074,611653034702238664 %N A302228 Number of 5Xn 0..1 arrays with every element equal to 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302228 Row 5 of A302224. %H A302228 R. H. Hardin, <a href="/A302228/b302228.txt">Table of n, a(n) for n = 1..210</a> %e A302228 Some solutions for n=5 %e A302228 ..0..1..1..0..0. .0..0..1..1..1. .0..0..1..0..1. .0..0..0..0..0 %e A302228 ..1..0..0..1..0. .1..1..0..0..0. .1..0..0..1..0. .0..1..1..0..0 %e A302228 ..1..1..0..1..1. .0..0..1..1..0. .1..1..0..1..1. .1..0..1..1..1 %e A302228 ..1..1..0..1..1. .0..0..1..0..0. .1..0..0..1..0. .1..0..0..1..0 %e A302228 ..0..0..0..0..1. .0..1..1..1..1. .1..1..0..0..1. .0..1..0..0..1 %Y A302228 Cf. A302224. %K A302228 nonn %O A302228 1,2 %A A302228 _R. H. Hardin_, Apr 03 2018