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 A301394 #6 Aug 20 2020 11:43:24 %S A301394 0,1,3,78,4857,885003,528025038,956047339302,5338842851150762, %T A301394 91544753173766016191,4821728266187979354515714 %N A301394 Number of n X n 0..1 arrays with every element equal to 2, 3, 4, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. %C A301394 Diagonal of A301400. %e A301394 Some solutions for n=5 %e A301394 ..0..0..1..1..0. .0..0..0..0..0. .0..0..0..0..1. .0..0..0..1..1 %e A301394 ..0..1..1..0..0. .0..0..1..0..0. .0..0..0..1..1. .0..0..1..1..1 %e A301394 ..0..1..1..0..1. .0..1..1..0..1. .0..0..0..1..1. .1..1..0..1..1 %e A301394 ..0..0..1..1..1. .0..0..0..1..1. .0..1..0..0..0. .1..0..0..1..1 %e A301394 ..0..0..1..1..1. .0..0..1..1..1. .1..1..0..0..0. .1..1..1..1..1 %Y A301394 Cf. A301400. %K A301394 nonn %O A301394 1,3 %A A301394 _R. H. Hardin_, Mar 20 2018