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 A207806 #7 Jul 22 2025 20:51:29 %S A207806 26,676,4374,43990,382288,3511534,31569510,285774964,2580956950, %T A207806 23333448086,210885788448,1906172464566,17228491782138, %U A207806 155715573550500,1407388340653890,12720361717357138,114970670286577872 %N A207806 Number of nX6 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 0 and 1 0 1 vertically. %C A207806 Column 6 of A207808 %H A207806 R. H. Hardin, <a href="/A207806/b207806.txt">Table of n, a(n) for n = 1..210</a> %e A207806 Some solutions for n=4 %e A207806 ..1..1..0..1..1..1....1..1..0..1..0..0....1..0..1..1..1..0....0..1..1..1..1..0 %e A207806 ..1..1..0..1..1..0....0..1..0..1..1..0....0..1..1..1..1..0....0..1..1..1..1..0 %e A207806 ..0..1..1..0..1..0....0..1..0..1..1..1....0..1..1..1..1..0....1..0..1..0..1..1 %e A207806 ..0..1..1..0..1..0....0..1..0..1..0..1....1..1..0..1..1..0....1..0..1..0..1..1 %K A207806 nonn %O A207806 1,1 %A A207806 _R. H. Hardin_ Feb 20 2012