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 A302673 #4 Apr 11 2018 12:02:03 %S A302673 0,1172,10660,106793,2320879,35549458,637088915,11181864782, %T A302673 188509564214,3339792969770,57406756149300,997632805281762, %U A302673 17363763785624592,300575131517843683,5229363965628293685,90736499929821199253 %N A302673 Number of 7Xn 0..1 arrays with every element equal to 1, 2, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302673 Row 7 of A302670. %H A302673 R. H. Hardin, <a href="/A302673/b302673.txt">Table of n, a(n) for n = 1..210</a> %e A302673 Some solutions for n=5 %e A302673 ..0..0..0..1..0. .0..0..0..1..0. .0..0..0..0..0. .0..0..0..1..1 %e A302673 ..1..0..1..0..1. .0..0..1..0..1. .0..0..1..1..0. .1..0..1..0..1 %e A302673 ..1..1..1..0..0. .1..0..1..0..0. .1..1..1..1..0. .0..1..1..0..0 %e A302673 ..1..1..1..0..1. .0..1..0..1..1. .0..0..0..0..1. .0..0..0..0..0 %e A302673 ..1..0..1..1..1. .1..1..0..0..1. .1..1..1..1..0. .1..1..1..1..1 %e A302673 ..0..0..1..0..1. .0..1..1..0..1. .1..0..0..1..1. .0..0..0..0..1 %e A302673 ..1..1..1..1..0. .1..0..0..1..0. .1..1..0..0..1. .0..0..1..1..1 %Y A302673 Cf. A302670. %K A302673 nonn %O A302673 1,2 %A A302673 _R. H. Hardin_, Apr 11 2018