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 A285145 #7 Apr 05 2020 21:34:32 %S A285145 0,2,113,11574,4551741,7586120602,52105131287528,1469435682255774972, %T A285145 168943399492409779855098,78854409689567939731003347822, %U A285145 148970519290227262688309540510302237 %N A285145 Number of n X n 0..1 arrays with the number of 1's horizontally or antidiagonally adjacent to some 0 one less than the number of 0's adjacent to some 1. %C A285145 Diagonal of A285152. %H A285145 R. H. Hardin, <a href="/A285145/b285145.txt">Table of n, a(n) for n = 1..12</a> %e A285145 Some solutions for n=4 %e A285145 ..1..0..0..1. .0..1..1..1. .0..1..0..1. .0..1..1..0. .0..1..1..1 %e A285145 ..0..1..0..0. .1..1..0..0. .0..1..1..1. .0..0..0..0. .0..1..1..0 %e A285145 ..0..1..1..0. .0..1..0..0. .1..0..0..0. .1..1..1..0. .0..0..1..0 %e A285145 ..1..1..1..1. .1..0..1..0. .0..0..1..0. .1..1..0..1. .0..1..1..1 %Y A285145 Cf. A285152. %K A285145 nonn %O A285145 1,2 %A A285145 _R. H. Hardin_, Apr 12 2017