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 A208366 #7 Jul 22 2025 21:17:49 %S A208366 16,256,1644,9999,67396,422541,2563359,15730896,96081144,582174000, %T A208366 3527156073,21366154944,129224742827,781136134575,4721445779732, %U A208366 28529589334000,172355128544728,1041178745668425,6289245172035000 %N A208366 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 0 1 0 vertically. %C A208366 Column 5 of A208369 %H A208366 R. H. Hardin, <a href="/A208366/b208366.txt">Table of n, a(n) for n = 1..210</a> %e A208366 Some solutions for n=4 %e A208366 ..1..1..0..1..1....0..1..0..1..1....1..0..1..1..1....0..1..1..1..1 %e A208366 ..1..1..0..1..1....1..0..1..0..1....0..1..1..0..0....0..1..0..1..1 %e A208366 ..0..1..0..1..0....1..0..1..0..0....0..1..1..1..1....0..1..1..1..0 %e A208366 ..0..1..0..1..0....1..0..1..0..1....0..1..1..1..1....0..1..1..0..1 %K A208366 nonn %O A208366 1,1 %A A208366 _R. H. Hardin_ Feb 25 2012