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 A297873 #4 Jan 07 2018 11:30:08 %S A297873 0,11,0,20,80,231,579,2437,7507,26278,91622,316406,1091518,3805139, %T A297873 13166620,45743807,158968332,552175778,1918002602,6665774473, %U A297873 23158033370,80468332463,279615402191,971597706573,3376114511226,11731585710994 %N A297873 Number of nX5 0..1 arrays with every element equal to 2, 3 or 5 king-move adjacent elements, with upper left element zero. %C A297873 Column 5 of A297876. %H A297873 R. H. Hardin, <a href="/A297873/b297873.txt">Table of n, a(n) for n = 1..210</a> %e A297873 Some solutions for n=7 %e A297873 ..0..0..1..0..0. .0..0..1..0..0. .0..0..0..1..1. .0..1..1..1..0 %e A297873 ..0..1..1..1..0. .0..1..1..1..0. .0..1..1..0..1. .0..0..1..0..0 %e A297873 ..0..1..0..1..0. .1..0..0..0..1. .1..1..0..0..1. .0..1..1..0..1 %e A297873 ..0..0..1..0..0. .0..1..1..1..0. .1..0..1..1..0. .1..0..0..1..1 %e A297873 ..1..1..1..1..1. .1..0..0..0..1. .0..0..1..0..0. .1..1..1..0..1 %e A297873 ..0..1..1..0..1. .0..1..1..1..0. .1..0..1..0..1. .1..0..1..0..1 %e A297873 ..0..0..1..0..0. .0..0..1..0..0. .1..1..0..1..1. .0..0..0..1..1 %Y A297873 Cf. A297876. %K A297873 nonn %O A297873 1,2 %A A297873 _R. H. Hardin_, Jan 07 2018