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 A302517 #4 Apr 09 2018 09:11:26 %S A302517 8,6,9,28,36,80,235,541,1115,2554,6095,13920,31216,71431,164589, %T A302517 375943,856294,1957963,4481840,10241792,23394379,53477141,122262891, %U A302517 279435298,638618663,1459697640,3336520448,7626024455,17430072821,39839300103 %N A302517 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302517 Row 4 of A302515. %H A302517 R. H. Hardin, <a href="/A302517/b302517.txt">Table of n, a(n) for n = 1..210</a> %F A302517 Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) +5*a(n-4) -a(n-5) -5*a(n-6) -4*a(n-7) for n>10 %e A302517 Some solutions for n=5 %e A302517 ..0..1..0..1..0. .0..1..1..1..0. .0..1..1..1..0. .0..1..0..1..1 %e A302517 ..0..0..1..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..0..0 %e A302517 ..0..1..0..1..0. .0..1..0..1..0. .0..1..0..0..0. .0..1..0..1..0 %e A302517 ..0..1..0..1..0. .0..1..1..1..0. .0..1..0..1..1. .0..1..0..1..0 %Y A302517 Cf. A302515. %K A302517 nonn %O A302517 1,1 %A A302517 _R. H. Hardin_, Apr 09 2018