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A250951 Number of (n+1) X (3+1) 0..1 arrays with no 2 X 2 subblock having its maximum diagonal element less than its minimum antidiagonal element.

%I A250951 #10 Nov 24 2018 08:11:25
%S A250951 209,2744,36016,472712,6204344,81431944,1068793208,14027896712,
%T A250951 184115958136,2416519505288,31716786410360,416282400363400,
%U A250951 5463700975560056,71711002733396360,941205958384596856
%N A250951 Number of (n+1) X (3+1) 0..1 arrays with no 2 X 2 subblock having its maximum diagonal element less than its minimum antidiagonal element.
%H A250951 R. H. Hardin, <a href="/A250951/b250951.txt">Table of n, a(n) for n = 1..210</a>
%F A250951 Empirical: a(n) = 15*a(n-1) - 24*a(n-2) - 8*a(n-3).
%F A250951 Empirical g.f.: x*(209 - 391*x - 128*x^2) / (1 - 15*x + 24*x^2 + 8*x^3). - _Colin Barker_, Nov 24 2018
%e A250951 Some solutions for n=3:
%e A250951   1 0 0 1    1 1 0 1    0 1 0 0    1 0 1 1    0 0 1 0
%e A250951   0 0 0 0    1 0 1 1    0 1 0 0    0 0 0 1    1 0 1 1
%e A250951   1 0 0 1    0 1 1 0    1 1 0 1    1 0 0 0    0 0 0 1
%e A250951   0 0 0 1    0 0 1 1    0 1 0 1    1 0 0 0    0 0 1 1
%Y A250951 Column 3 of A250956.
%K A250951 nonn
%O A250951 1,1
%A A250951 _R. H. Hardin_, Nov 28 2014