# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a250952 Showing 1-1 of 1 %I A250952 #8 Nov 24 2018 08:11:32 %S A250952 780,19208,472712,11633448,286298344,7045780240,173396103624, %T A250952 4267264603784,105017049454880,2584461405506568,63603393841083832, %U A250952 1565274567258578128,38521285153870175304,948005826546231120680 %N A250952 Number of (n+1) X (4+1) 0..1 arrays with no 2 X 2 subblock having its maximum diagonal element less than its minimum antidiagonal element. %H A250952 R. H. Hardin, Table of n, a(n) for n = 1..210 %F A250952 Empirical: a(n) = 27*a(n-1) - 57*a(n-2) - 46*a(n-3) + 30*a(n-4). %F A250952 Empirical g.f.: 4*x*(195 - 463*x - 361*x^2 + 240*x^3) / (1 - 27*x + 57*x^2 + 46*x^3 - 30*x^4). - _Colin Barker_, Nov 24 2018 %e A250952 Some solutions for n=2: %e A250952 ..0..1..1..1..0....0..1..0..0..0....0..1..0..1..0....1..0..1..1..1 %e A250952 ..1..1..0..0..0....0..0..0..0..0....1..1..0..0..1....1..1..1..0..0 %e A250952 ..0..0..0..1..1....0..1..0..0..1....1..0..0..0..1....1..1..1..0..0 %Y A250952 Column 4 of A250956. %K A250952 nonn %O A250952 1,1 %A A250952 _R. H. Hardin_, Nov 28 2014 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE