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%I #9 Apr 14 2018 13:11:16
%S 64,424,2248,13096,73288,417256,2358280,13370536,75704776,428889448,
%T 2429192584,13760163880,77941013320,441485755624,2500712951560,
%U 14164866483112,80234377893064,454473710492776,2574286780013704
%N Number of (n+1) X 2 0..3 arrays with every 2 X 2 subblock singular.
%C Column 1 of A184773.
%H R. H. Hardin, <a href="/A184765/b184765.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 5*a(n-1) + 8*a(n-2) - 24*a(n-3).
%F Empirical g.f.: 8*x*(8 + 13*x - 48*x^2) / (1 - 5*x - 8*x^2 + 24*x^3). - _Colin Barker_, Apr 14 2018
%e Some solutions for 3 X 2:
%e ..1..2....0..1....3..3....0..0....2..0....0..0....1..0....0..0....2..2....0..0
%e ..0..0....0..0....1..1....3..2....2..0....1..2....0..0....2..0....3..3....1..1
%e ..0..1....0..3....0..0....3..2....3..0....0..0....3..1....1..0....1..1....2..2
%Y Cf. A184773.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 21 2011