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 A296828 #6 Apr 26 2020 21:07:23 %S A296828 2,6,43,573,14379,706534,67007971,12228697715,4321362259224, %T A296828 2948102949160889 %N A296828 Number of n X n 0..1 arrays with each 1 adjacent to 0, 3 or 5 king-move neighboring 1's. %C A296828 Diagonal of A296834. %e A296828 Some solutions for n=5 %e A296828 ..1..0..0..0..0. .1..0..0..1..0. .0..0..1..0..0. .0..0..0..0..0 %e A296828 ..0..0..0..0..1. .0..0..0..0..0. .0..0..0..0..0. .1..1..0..0..1 %e A296828 ..1..0..0..0..0. .0..0..1..0..1. .1..1..0..0..1. .1..1..0..0..0 %e A296828 ..0..0..0..0..1. .0..0..0..0..0. .1..1..0..0..0. .0..0..0..0..0 %e A296828 ..1..0..1..0..0. .1..0..1..0..1. .1..1..0..0..0. .0..1..0..0..0 %Y A296828 Cf. A296834. %K A296828 nonn %O A296828 1,1 %A A296828 _R. H. Hardin_, Dec 21 2017