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A251096 Number of (n+1)X(4+1) 0..1 arrays with no 2X2 subblock having its minimum diagonal element less than its minimum antidiagonal element.

%I A251096 #6 Jul 23 2025 13:03:50
%S A251096 406,5817,82814,1175519,16697127,237288487,3372537762,47933018061,
%T A251096 681254534234,9682407527191,137612328359012,1955831221215641,
%U A251096 27797479224555547,395074912980985813,5615048233207846538
%N A251096 Number of (n+1)X(4+1) 0..1 arrays with no 2X2 subblock having its minimum diagonal element less than its minimum antidiagonal element.
%C A251096 Column 4 of A251100
%H A251096 R. H. Hardin, <a href="/A251096/b251096.txt">Table of n, a(n) for n = 1..210</a>
%F A251096 Empirical: a(n) = 32*a(n-1) -408*a(n-2) +3073*a(n-3) -15730*a(n-4) +58157*a(n-5) -160070*a(n-6) +333703*a(n-7) -532992*a(n-8) +656691*a(n-9) -625063*a(n-10) +457960*a(n-11) -256393*a(n-12) +108609*a(n-13) -34260*a(n-14) +7752*a(n-15) -1136*a(n-16) +80*a(n-17)
%e A251096 Some solutions for n=3
%e A251096 ..0..0..0..1..1....1..0..0..1..1....1..0..1..0..0....1..0..1..0..0
%e A251096 ..1..0..0..0..1....1..0..0..0..0....0..0..0..0..1....1..0..0..1..1
%e A251096 ..0..0..0..0..0....0..1..0..0..0....1..1..1..0..0....1..0..0..0..1
%e A251096 ..1..1..1..0..0....0..0..1..1..0....1..1..1..1..0....1..0..1..0..1
%K A251096 nonn
%O A251096 1,1
%A A251096 _R. H. Hardin_, Nov 29 2014