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%I
%S 47,181,749,3254,14199,62031,271125,1185255,5181921,22656123,99057573,
%T 433104831,1893650697,8279562627,36200555181,158278967559,
%U 692040086289,3025793769291,13229621235765,57843625143375,252908600485401
%N Number of (n+1) X 3 0..1 arrays with the determinants of 2 X 2 subblocks nondecreasing rightwards and downwards.
%C Column 2 of A204616.
%H R. H. Hardin, <a href="/A204610/b204610.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 5*a(n-2) - 12*a(n-3) + 12*a(n-4) for n>7.
%F Empirical g.f.: x*(47 - 101*x - 102*x^2 + 229*x^3 + 28*x^4 - 77*x^5 - 6*x^6) / ((1 - x)*(1 - 2*x)*(1 - 3*x - 6*x^2)). - _Colin Barker_, Jun 07 2018
%e Some solutions for n=4:
%e ..0..1..1....1..0..0....0..1..1....1..0..1....0..1..1....1..0..0....0..1..0
%e ..1..0..0....0..0..1....1..0..0....0..0..1....0..0..0....1..0..0....0..1..0
%e ..1..0..0....0..0..1....0..0..1....0..0..1....0..1..0....0..0..0....0..1..0
%e ..1..0..0....1..0..1....1..0..1....1..0..0....0..0..0....1..1..0....0..0..0
%e ..0..0..1....1..0..1....0..0..0....1..0..1....0..1..1....1..1..0....1..1..0
%Y Cf. A204616.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 17 2012
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