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 A303078 #6 Sep 16 2020 19:02:18 %S A303078 1,2,32,90,11767,409478,266882021,218955384065,942790501392266 %N A303078 Number of n X n 0..1 arrays with every element equal to 0, 2, 3, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A303078 Diagonal of A303084. %e A303078 Some solutions for n=5 %e A303078 ..0..1..1..1..1. .0..0..1..1..1. .0..0..1..0..0. .0..0..1..0..0 %e A303078 ..0..1..1..1..0. .0..0..0..1..1. .1..0..0..0..0. .1..0..0..0..1 %e A303078 ..0..1..0..1..1. .0..0..1..1..0. .1..0..0..0..1. .1..0..0..0..1 %e A303078 ..1..1..1..1..0. .0..0..1..1..1. .1..0..1..0..1. .0..0..1..0..1 %e A303078 ..0..1..1..1..1. .1..0..0..1..1. .0..0..0..0..0. .0..0..0..0..0 %Y A303078 Cf. A303084. %K A303078 nonn %O A303078 1,2 %A A303078 _R. H. Hardin_, Apr 18 2018