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 A228757 #7 Sep 03 2013 23:53:10 %S A228757 16,55,723,4808,43862,342207,2876170,23326164,192379841,1574217212, %T A228757 12928573892,106000461919,869759215471,7134075563384,58525595955046, %U A228757 480089753747591,3938341082031018,32307082900690396,265023929648410933 %N A228757 Number of 5Xn binary arrays with top left element equal to 1 and no two ones adjacent horizontally or antidiagonally. %C A228757 Row 5 of A228754 %H A228757 R. H. Hardin, <a href="/A228757/b228757.txt">Table of n, a(n) for n = 1..210</a> %F A228757 Empirical: a(n) = a(n-1) +49*a(n-2) +107*a(n-3) -154*a(n-4) -404*a(n-5) +250*a(n-6) +472*a(n-7) -278*a(n-8) -168*a(n-9) +131*a(n-10) -9*a(n-11) -7*a(n-12) +a(n-13) %e A228757 Some solutions for n=4 %e A228757 ..1..0..1..0....1..0..1..0....1..0..0..0....1..0..0..0....1..0..0..0 %e A228757 ..0..0..0..0....1..0..1..0....1..0..0..0....0..0..0..1....0..0..1..0 %e A228757 ..1..0..0..1....1..0..0..0....0..0..0..0....1..0..0..0....1..0..0..1 %e A228757 ..1..0..0..1....0..0..1..0....0..0..0..0....1..0..1..0....1..0..0..1 %e A228757 ..1..0..0..0....1..0..0..0....1..0..0..1....0..0..0..0....0..0..0..1 %K A228757 nonn %O A228757 1,1 %A A228757 _R. H. Hardin_ Sep 02 2013