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 A208696 #7 Jul 22 2025 21:28:16 %S A208696 22,484,2706,24086,177488,1415508,10934750,85697362,667262804, %T A208696 5207958764,40607176444,316775073124,2470717292796,19272100725330, %U A208696 150320036967880,1172492187142646,9145360490517122,71333468695248480,556397961419606324 %N A208696 Number of nX6 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 1 0 and 1 0 1 vertically. %C A208696 Column 6 of A208698 %H A208696 R. H. Hardin, <a href="/A208696/b208696.txt">Table of n, a(n) for n = 1..210</a> %e A208696 Some solutions for n=4 %e A208696 ..1..0..1..1..0..1....1..1..1..1..1..1....1..0..1..0..1..0....1..1..0..1..0..1 %e A208696 ..0..1..0..1..1..0....1..0..1..0..1..0....0..1..0..1..0..1....0..1..0..1..0..1 %e A208696 ..0..1..0..1..1..0....0..0..0..0..0..0....0..1..0..1..0..1....0..1..0..1..0..1 %e A208696 ..1..1..1..1..1..1....0..1..0..1..0..1....1..0..1..1..0..1....1..0..1..1..0..1 %K A208696 nonn %O A208696 1,1 %A A208696 _R. H. Hardin_ Mar 01 2012