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%I #7 Nov 15 2018 08:37:55
%S 24,60,142,329,758,1743,4009,9223,21227,48864,112503,259042,596486,
%T 1373534,3162900,7283395,16771972,38622017,88937775,204803649,
%U 471616777,1086027506,2500877597,5758959852,13261592356,30538471600,70323248330
%N Number of (n+1) X (2+1) 0..1 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.
%H R. H. Hardin, <a href="/A250577/b250577.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) - 3*a(n-2) - 5*a(n-3) + 8*a(n-4) - 3*a(n-5).
%F Empirical g.f.: x*(24 - 36*x - 26*x^2 + 61*x^3 - 24*x^4) / ((1 - x)^3*(1 - x - 3*x^2)). - _Colin Barker_, Nov 15 2018
%e Some solutions for n=6:
%e ..0..0..1....1..1..1....1..1..1....0..0..1....0..0..1....0..0..1....0..1..1
%e ..1..0..1....0..1..1....1..1..1....1..0..1....1..1..1....0..0..1....0..1..1
%e ..0..1..0....1..1..1....0..1..1....0..1..1....0..1..1....0..1..1....1..1..1
%e ..1..0..1....0..1..1....1..1..1....1..0..1....0..1..1....1..0..1....0..1..1
%e ..0..1..1....0..1..1....0..1..1....0..1..1....1..0..1....0..1..1....0..1..1
%e ..0..1..1....0..1..1....0..1..1....0..1..1....0..1..1....1..0..1....1..0..1
%e ..0..1..1....0..1..1....0..1..1....1..0..1....1..1..1....0..1..0....0..1..0
%Y Column 2 of A250583.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 25 2014
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