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 A208015 #8 Jun 26 2018 14:08:31 %S A208015 12,144,420,1943,5952,16224,55624,181192,545140,1737120,5591900, %T A208015 17461000,55016920,175036148,552196708,1741059012,5511897568, %U A208015 17422085700,55006038672,173881945232,549639384692,1736473292204,5487493400532 %N A208015 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 0 1 1 vertically. %C A208015 Row 5 of A208013. %H A208015 R. H. Hardin, <a href="/A208015/b208015.txt">Table of n, a(n) for n = 1..210</a> %F A208015 Empirical: a(n) = a(n-1) + 23*a(n-3) + 6*a(n-4) + 6*a(n-5) - 108*a(n-6) - 72*a(n-7) + 216*a(n-9) for n>11. %F A208015 Empirical g.f.: x*(12 + 132*x + 276*x^2 + 1247*x^3 + 625*x^4 - 324*x^5 - 7377*x^6 - 9090*x^7 - 846*x^8 + 17064*x^9 + 7884*x^10) / (1 - x - 23*x^3 - 6*x^4 - 6*x^5 + 108*x^6 + 72*x^7 - 216*x^9). - _Colin Barker_, Jun 26 2018 %e A208015 Some solutions for n=4: %e A208015 ..1..0..0..1....0..1..1..1....0..0..1..0....1..1..0..0....0..0..1..1 %e A208015 ..0..1..1..0....0..1..1..0....0..1..1..1....1..1..1..0....1..1..1..0 %e A208015 ..1..0..0..1....0..1..0..0....0..0..1..0....0..1..0..0....0..0..1..0 %e A208015 ..0..1..1..0....0..0..1..0....0..1..0..0....1..1..1..0....1..1..0..0 %e A208015 ..1..0..0..1....0..1..0..0....0..0..1..0....0..1..0..0....0..0..1..0 %Y A208015 Cf. A208013. %K A208015 nonn %O A208015 1,1 %A A208015 _R. H. Hardin_, Feb 22 2012