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%I #9 Mar 16 2018 10:26:42
%S 4,16,53,155,418,1066,2611,6205,14408,32852,73825,163951,360574,
%T 786574,1704095,3670193,7864516,16777432,35651821,75497731,159383834,
%U 335544626,704643403,1476395365,3087008128,6442451356,13421773241,27917287895
%N Number of n X 2 0..1 arrays with row sums and column sums unimodal.
%C Column 2 of A223716.
%H R. H. Hardin, <a href="/A223711/b223711.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) - 19*a(n-2) + 25*a(n-3) - 16*a(n-4) + 4*a(n-5).
%F Conjectures from _Colin Barker_, Mar 16 2018: (Start)
%F G.f.: x*(2 - 3*x + 2*x^2)^2 / ((1 - x)^3*(1 - 2*x)^2).
%F a(n) = (-2*(2^(3+n)-9) + (5+2^(3+n))*n + n^2) / 2.
%F (End)
%e Some solutions for n=3:
%e ..1..0....0..0....1..1....0..0....1..0....0..1....1..0....0..0....0..0....0..0
%e ..0..1....1..0....1..0....0..1....1..1....0..1....0..1....0..1....1..1....1..0
%e ..1..0....1..0....0..1....1..0....0..0....0..0....0..0....1..1....1..0....0..0
%Y Cf. A223716.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 26 2013
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