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 A297228 #4 Dec 27 2017 15:41:00 %S A297228 1,88,564,2720,30946,261939,1918732,16176806,134671502,1084005062, %T A297228 8855022968,72556284402,592076260322,4833986775520,39491897603294, %U A297228 322560160507073,2634426639664265,21517102473205131,175744528043164291 %N A297228 Number of 6Xn 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s. %C A297228 Row 6 of A297224. %H A297228 R. H. Hardin, <a href="/A297228/b297228.txt">Table of n, a(n) for n = 1..210</a> %e A297228 Some solutions for n=5 %e A297228 ..1..1..0..1..1. .1..1..0..0..0. .0..1..0..1..1. .0..0..0..1..1 %e A297228 ..0..0..0..0..0. .0..0..0..0..0. .1..0..0..0..0. .0..1..0..0..1 %e A297228 ..0..0..0..0..0. .1..1..0..1..1. .0..0..1..1..0. .1..0..0..1..0 %e A297228 ..0..1..0..0..1. .0..0..0..0..0. .0..0..0..1..1. .0..1..0..0..0 %e A297228 ..1..0..0..1..0. .0..0..0..0..0. .0..0..0..0..0. .1..0..0..0..0 %e A297228 ..1..1..0..0..0. .1..1..0..0..0. .0..1..1..0..0. .0..0..0..0..0 %Y A297228 Cf. A297224. %K A297228 nonn %O A297228 1,2 %A A297228 _R. H. Hardin_, Dec 27 2017