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 A318070 #4 Aug 15 2018 13:17:36 %S A318070 4,10,18,41,81,179,404,893,2000,4516,10125,22737,51181,115034,258515, %T A318070 581380,1307094,2938317,6606445,14853275,33392840,75076165,168791772, %U A318070 379483956,853176349,1918162541,4312510121,9695613622,21798217755 %N A318070 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. %C A318070 Column 3 of A318075. %H A318070 R. H. Hardin, <a href="/A318070/b318070.txt">Table of n, a(n) for n = 1..210</a> %F A318070 Empirical: a(n) = 2*a(n-1) +a(n-2) +a(n-3) -3*a(n-4) -6*a(n-5) +6*a(n-6) for n>10 %e A318070 Some solutions for n=5 %e A318070 ..0..1..1. .0..0..0. .0..0..1. .0..1..1. .0..0..0. .0..0..0. .0..0..0 %e A318070 ..1..0..0. .0..0..0. .0..1..1. .1..1..1. .0..0..0. .0..0..0. .0..0..1 %e A318070 ..1..1..0. .0..0..0. .1..1..1. .1..1..1. .0..0..1. .1..1..1. .0..1..1 %e A318070 ..0..0..0. .0..1..0. .0..0..0. .1..0..1. .0..1..1. .1..1..1. .1..1..1 %e A318070 ..0..0..1. .1..0..0. .0..0..1. .0..1..1. .1..1..0. .1..1..1. .0..0..0 %Y A318070 Cf. A318075. %K A318070 nonn %O A318070 1,1 %A A318070 _R. H. Hardin_, Aug 15 2018