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 A285756 #6 Apr 05 2020 23:24:11 %S A285756 0,2896,265920,27339964,3077883556,345505561776,40895629554933, %T A285756 4788769986049492,578161651518199128,69329034539728070792, %U A285756 8460129656506891963059,1028996276834209548728154 %N A285756 Number of 7 X n 0..1 arrays with the number of 1's horizontally, diagonally or antidiagonally adjacent to some 0 one less than the number of 0's adjacent to some 1. %C A285756 Row 7 of A285750. %H A285756 R. H. Hardin, <a href="/A285756/b285756.txt">Table of n, a(n) for n = 1..14</a> %e A285756 Some solutions for n=2 %e A285756 ..0..0. .0..1. .1..0. .0..0. .1..1. .0..0. .1..1. .1..1. .1..0. .1..0 %e A285756 ..0..0. .1..0. .1..1. .1..1. .1..0. .0..0. .0..0. .1..0. .0..1. .1..0 %e A285756 ..0..0. .1..0. .0..0. .1..1. .0..1. .0..1. .0..1. .0..0. .0..1. .1..0 %e A285756 ..1..0. .1..1. .0..1. .1..0. .1..0. .0..0. .0..0. .0..0. .0..0. .0..0 %e A285756 ..1..0. .0..0. .0..0. .1..0. .0..1. .1..1. .0..1. .1..0. .0..0. .0..0 %e A285756 ..1..1. .1..0. .0..0. .0..0. .0..0. .1..0. .1..0. .0..0. .1..1. .1..0 %e A285756 ..0..0. .0..0. .0..0. .0..1. .1..0. .0..1. .1..0. .1..1. .1..1. .1..1 %Y A285756 Cf. A285750. %K A285756 nonn %O A285756 1,2 %A A285756 _R. H. Hardin_, Apr 25 2017