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 A295914 #8 Feb 22 2019 10:04:47 %S A295914 8,28,115,467,1880,7604,30721,124117,501512,2026304,8187195,33079959, %T A295914 133657824,540037688,2181994609,8816237625,35621557528,143927081684, %U A295914 581530015059,2349642293451,9493609553944,38358444014860,154985331853649 %N A295914 Number of n X 4 0..1 arrays with each 1 adjacent to 0 or 3 king-move neighboring 1s. %H A295914 R. H. Hardin, <a href="/A295914/b295914.txt">Table of n, a(n) for n = 1..210</a> %F A295914 Empirical: a(n) = 2*a(n-1) + 7*a(n-2) + 6*a(n-3) - 3*a(n-4) - 4*a(n-5) + a(n-6). %F A295914 Empirical g.f.: x*(8 + 12*x + 3*x^2 - 7*x^3 - 3*x^4 + x^5) / ((1 + x)*(1 - 3*x - 4*x^2 - 2*x^3 + 5*x^4 - x^5)). - _Colin Barker_, Feb 22 2019 %e A295914 Some solutions for n=7: %e A295914 ..1..0..0..0. .0..1..0..0. .0..0..0..1. .0..0..0..1. .0..0..0..1 %e A295914 ..0..0..1..0. .0..0..0..0. .1..0..0..0. .1..0..0..0. .1..1..0..0 %e A295914 ..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..0. .1..1..0..0 %e A295914 ..1..1..0..0. .0..0..0..0. .0..1..0..1. .0..0..0..0. .0..0..0..1 %e A295914 ..1..1..0..0. .0..0..1..0. .0..0..0..0. .0..0..0..0. .1..0..0..0 %e A295914 ..0..0..0..1. .1..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0 %e A295914 ..0..0..0..0. .0..0..1..0. .0..0..0..0. .0..0..0..1. .0..1..0..0 %Y A295914 Column 4 of A295918. %K A295914 nonn %O A295914 1,1 %A A295914 _R. H. Hardin_, Nov 29 2017