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 A293081 #6 Apr 05 2020 23:37:04 %S A293081 0,0,1,10,60,304,1420,6312,27167,114412,474563,1947098,7925708, %T A293081 32072580,129213082,518818124,2077775396,8304424080,33138971978, %U A293081 132078954532,525904271587,2092410377864,8320012474033,33066905278394,131371155380369 %N A293081 Number of n X 2 0..1 arrays with the number of 1's horizontally or antidiagonally adjacent to some 0 two less than the number of 0's adjacent to some 1. %C A293081 Column 2 of A293087. %H A293081 R. H. Hardin, <a href="/A293081/b293081.txt">Table of n, a(n) for n = 1..210</a> %e A293081 All solutions for n=4 %e A293081 ..0..1. .1..0. .0..0. .0..1. .0..1. .0..1. .0..1. .0..1. .0..0. .0..0 %e A293081 ..0..0. .0..1. .1..0. .0..0. .0..0. .0..0. .0..1. .0..0. .1..0. .0..1 %e A293081 ..1..0. .0..0. .0..0. .0..1. .1..0. .1..0. .0..0. .0..0. .0..1. .0..0 %e A293081 ..1..0. .1..0. .1..0. .0..0. .0..0. .0..1. .1..0. .1..0. .0..0. .1..0 %Y A293081 Cf. A293087. %K A293081 nonn %O A293081 1,4 %A A293081 _R. H. Hardin_, Sep 30 2017