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 A285745 #7 Apr 05 2020 23:17:24 %S A285745 1,8,105,550,5105,30918,265920,1773432,14632372,103605826,834224969, %T A285745 6128787272,48666035225,365893476096,2883831290602,22005412864334, %U A285745 172812531531152,1331535174196624,10442072847350585,80985489140322402 %N A285745 Number of n X 3 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 A285745 Column 3 of A285750. %H A285745 R. H. Hardin, <a href="/A285745/b285745.txt">Table of n, a(n) for n = 1..210</a> %e A285745 Some solutions for n=4 %e A285745 ..0..0..0. .1..1..1. .1..1..0. .0..0..1. .0..1..1. .0..0..0. .1..0..1 %e A285745 ..1..1..0. .0..0..0. .1..0..0. .0..1..0. .1..1..1. .0..1..1. .0..0..0 %e A285745 ..1..0..1. .0..0..0. .0..0..0. .1..0..1. .1..1..0. .1..0..1. .0..0..0 %e A285745 ..1..0..0. .0..0..1. .1..0..0. .0..0..1. .0..0..0. .0..0..1. .1..0..0 %Y A285745 Cf. A285750. %K A285745 nonn %O A285745 1,2 %A A285745 _R. H. Hardin_, Apr 25 2017