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 A303257 #4 Apr 20 2018 11:11:47 %S A303257 0,361,5918,55624,1105676,19457754,322544617,5622650429,96079232228, %T A303257 1646124445916,28299650557400,485285360460841,8326738600567856, %U A303257 142906680823826208,2452047535254667099,42076285291701652140 %N A303257 Number of 6Xn 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A303257 Row 6 of A303254. %H A303257 R. H. Hardin, <a href="/A303257/b303257.txt">Table of n, a(n) for n = 1..210</a> %e A303257 Some solutions for n=5 %e A303257 ..0..0..0..1..1. .0..0..0..0..1. .0..0..0..0..0. .0..0..0..1..1 %e A303257 ..1..0..0..1..1. .1..0..0..1..1. .0..0..1..1..0. .1..0..1..0..0 %e A303257 ..0..1..0..1..0. .0..1..0..1..1. .0..0..0..1..1. .1..1..1..1..0 %e A303257 ..0..1..0..0..0. .1..0..1..1..0. .0..0..0..1..1. .1..1..1..0..0 %e A303257 ..0..0..1..0..0. .1..0..1..0..0. .0..0..0..1..1. .0..0..1..0..1 %e A303257 ..0..1..0..1..0. .1..1..0..1..1. .1..1..0..1..1. .1..1..1..1..0 %Y A303257 Cf. A303254. %K A303257 nonn %O A303257 1,2 %A A303257 _R. H. Hardin_, Apr 20 2018