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 A302726 #4 Apr 12 2018 10:53:06 %S A302726 5,45,162,689,4505,20842,104969,623549,3195095,16779202,94570299, %T A302726 502818683,2684335804,14798497776,79585694357,428251526577, %U A302726 2337808909399,12622803157240,68178468555088,370527376656027,2003864441765404 %N A302726 Number of nX6 0..1 arrays with every element equal to 1, 2, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302726 Column 6 of A302728. %H A302726 R. H. Hardin, <a href="/A302726/b302726.txt">Table of n, a(n) for n = 1..210</a> %e A302726 Some solutions for n=5 %e A302726 ..0..1..1..1..0..0. .0..0..0..1..0..0. .0..1..1..0..1..1. .0..0..0..1..1..1 %e A302726 ..1..0..0..0..1..1. .1..1..1..0..1..1. .0..0..1..0..0..1. .0..1..0..1..0..1 %e A302726 ..1..0..1..0..1..0. .1..0..1..0..1..0. .1..0..1..0..1..0. .1..1..0..0..0..1 %e A302726 ..0..1..1..0..0..0. .0..0..1..0..0..1. .1..1..1..1..0..0. .0..0..1..1..1..0 %e A302726 ..0..0..1..0..0..0. .0..1..1..0..1..1. .0..0..0..0..1..1. .0..1..0..1..0..1 %Y A302726 Cf. A302728. %K A302726 nonn %O A302726 1,1 %A A302726 _R. H. Hardin_, Apr 12 2018