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 A207941 #7 Jul 22 2025 21:01:48 %S A207941 10,100,350,1271,5594,25490,121313,584386,2841676,13864995,67793828, %T A207941 331778574,1624527917,7956223332,38970988538,190898358977, %U A207941 935140523244,4580980652676,22441074230301,109933649821120,538540783077848 %N A207941 Number of 5Xn 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 1 0 vertically. %C A207941 Row 5 of A207938 %H A207941 R. H. Hardin, <a href="/A207941/b207941.txt">Table of n, a(n) for n = 1..210</a> %F A207941 Empirical: a(n) = 8*a(n-1) -5*a(n-2) -82*a(n-3) +113*a(n-4) +341*a(n-5) -502*a(n-6) -765*a(n-7) +943*a(n-8) +998*a(n-9) -797*a(n-10) -709*a(n-11) +275*a(n-12) +233*a(n-13) -26*a(n-14) -24*a(n-15) for n>16 %e A207941 Some solutions for n=4 %e A207941 ..0..1..1..0....0..0..0..0....1..0..1..1....1..0..1..0....1..1..1..1 %e A207941 ..1..1..0..1....1..0..1..1....1..1..0..1....0..1..1..0....1..0..1..0 %e A207941 ..1..1..1..1....0..0..0..0....1..1..1..1....1..0..1..0....1..1..1..1 %e A207941 ..1..1..1..1....0..0..0..0....1..1..1..1....1..1..1..0....1..0..1..1 %e A207941 ..1..1..1..1....0..0..0..0....1..1..1..1....1..1..1..0....1..0..1..1 %K A207941 nonn %O A207941 1,1 %A A207941 _R. H. Hardin_ Feb 21 2012