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 A302159 #4 Apr 02 2018 14:46:39 %S A302159 5,17,12,29,73,156,361,865,1970,4530,10571,24394,56204,130230,301221, %T A302159 695541,1608549,3720177,8597848,19876759,45959426,106246321,245619039, %U A302159 567865144,1312830532,3035049693,7016724012,16221856134,37502724170 %N A302159 Number of nX4 0..1 arrays with every element equal to 0, 1 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302159 Column 4 of A302163. %H A302159 R. H. Hardin, <a href="/A302159/b302159.txt">Table of n, a(n) for n = 1..210</a> %F A302159 Empirical: a(n) = a(n-1) +a(n-2) +6*a(n-3) -4*a(n-5) -7*a(n-6) -a(n-7) +3*a(n-8) +2*a(n-9) -a(n-10) -4*a(n-11) -3*a(n-12) +a(n-13) +2*a(n-14) +2*a(n-15) for n>19 %e A302159 Some solutions for n=5 %e A302159 ..0..0..1..1. .0..0..1..1. .0..1..0..1. .0..1..0..1. .0..1..0..1 %e A302159 ..0..1..0..1. .0..1..0..1. .0..1..0..0. .1..1..0..1. .0..1..1..0 %e A302159 ..0..1..0..1. .0..1..0..1. .0..1..0..1. .0..1..0..0. .1..0..1..0 %e A302159 ..1..1..0..0. .0..1..0..0. .0..1..0..1. .0..1..0..1. .1..0..1..0 %e A302159 ..0..1..0..1. .0..1..0..1. .0..1..0..1. .0..1..0..1. .1..0..0..1 %Y A302159 Cf. A302163. %K A302159 nonn %O A302159 1,1 %A A302159 _R. H. Hardin_, Apr 02 2018