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 A297320 #4 Dec 28 2017 07:32:48 %S A297320 1,1897,85041,1717882,90535227,4869858862,197589351469,8462603863772, %T A297320 387143404127578,17208423873690915,757092974470971658, %U A297320 33594816998930823407,1491858261000140438998,66127149761814467849317 %N A297320 Number of 7Xn 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 or 2 neighboring 1s. %C A297320 Row 7 of A297314. %H A297320 R. H. Hardin, <a href="/A297320/b297320.txt">Table of n, a(n) for n = 1..210</a> %e A297320 Some solutions for n=5 %e A297320 ..0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0 %e A297320 ..0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..0..0 %e A297320 ..0..0..0..0..1. .0..0..0..0..0. .0..0..0..0..0. .0..0..0..1..1 %e A297320 ..0..1..0..1..0. .0..0..1..1..1. .0..1..0..0..0. .0..1..0..1..0 %e A297320 ..1..1..0..0..0. .0..1..0..1..0. .1..1..1..0..0. .1..0..0..0..0 %e A297320 ..1..1..1..0..0. .1..0..0..1..1. .0..0..0..0..0. .0..0..0..0..0 %e A297320 ..0..0..0..1..1. .0..0..0..1..0. .0..1..1..1..1. .0..0..1..1..1 %Y A297320 Cf. A297314. %K A297320 nonn %O A297320 1,2 %A A297320 _R. H. Hardin_, Dec 28 2017