|
%I #7 Nov 25 2018 09:35:23
%S 41,212,1109,5817,30517,160086,839758,4405079,23107524,121214121,
%T 635847599,3335437865,17496560104,91780937840,481451239589,
%U 2525527648328,13248049600905,69494712657097,364545365754237,1912279634115658
%N Number of (n+1) X (2+1) 0..1 arrays with no 2 X 2 subblock having its minimum diagonal element less than its minimum antidiagonal element.
%H R. H. Hardin, <a href="/A251094/b251094.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) - 11*a(n-2) + 10*a(n-3) - 3*a(n-4).
%F Empirical g.f.: x*(41 - 75*x + 76*x^2 - 24*x^3) / (1 - 7*x + 11*x^2 - 10*x^3 + 3*x^4). - _Colin Barker_, Nov 25 2018
%e Some solutions for n=4:
%e ..0..0..0....0..0..1....1..0..1....1..1..0....1..0..1....1..0..0....0..0..0
%e ..1..0..0....0..0..0....1..0..1....0..1..1....0..0..0....1..0..0....1..1..0
%e ..0..1..1....0..0..1....1..0..0....0..0..0....0..0..1....0..0..0....0..0..0
%e ..0..0..1....1..0..0....0..0..0....1..1..1....1..0..0....1..0..1....1..0..0
%e ..1..0..1....0..1..0....0..1..1....0..0..0....0..1..0....0..0..0....0..0..0
%Y Column 2 of A251100.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 29 2014
| 