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 A207180 #7 Jul 22 2025 20:05:12 %S A207180 44,1936,44065,981850,23471595,567046841,13575513917,324280404464, %T A207180 7753960008192,185490886984435,4436906789153102,106121193817646599, %U A207180 2538197480774276123,60709250545517745427,1452061508622073819918 %N A207180 Number of nX6 0..1 arrays avoiding 0 0 0 horizontally and 0 1 0 vertically. %C A207180 Column 6 of A207182 %H A207180 R. H. Hardin, <a href="/A207180/b207180.txt">Table of n, a(n) for n = 1..210</a> %e A207180 Some solutions for n=4 %e A207180 ..1..0..1..1..1..0....0..0..1..1..1..1....0..0..1..1..0..1....1..1..1..1..1..1 %e A207180 ..0..1..0..1..1..0....0..1..0..1..0..1....0..0..1..1..0..0....1..1..1..1..0..1 %e A207180 ..0..1..1..1..0..1....1..1..1..0..1..0....1..1..0..0..1..1....1..1..1..1..1..1 %e A207180 ..0..0..1..1..1..1....1..0..1..0..1..0....1..1..0..0..1..1....1..1..1..1..1..1 %K A207180 nonn %O A207180 1,1 %A A207180 _R. H. Hardin_ Feb 15 2012