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%I #9 Apr 04 2018 12:09:32
%S 216,3552,57966,948164,15497634,253372446,4142036148,67714639662,
%T 1106996131802,18097205612196,295853182740306,4836611736951630,
%U 79068975444380772,1292620478037357518,21131773136239117962
%N Half the number of (n+1) X 3 0..2 arrays with no 2 X 2 subblock having sum 4.
%C Column 2 of A183792.
%H R. H. Hardin, <a href="/A183785/b183785.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 12*a(n-1) + 90*a(n-2) - 279*a(n-3) - 618*a(n-4) + 2092*a(n-5) - 1344*a(n-6).
%F Empirical g.f.: 2*x*(108 + 480*x - 2049*x^2 - 3422*x^3 + 13611*x^4 - 9072*x^5) / (1 - 12*x - 90*x^2 + 279*x^3 + 618*x^4 - 2092*x^5 + 1344*x^6). - _Colin Barker_, Apr 04 2018
%e Some solutions for 5 X 3:
%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0
%e ..1..1..2....1..2..1....1..2..1....1..1..1....1..0..2....0..0..0....2..1..0
%e ..1..0..0....2..1..2....2..2..1....2..1..2....1..1..0....2..1..0....0..0..1
%e ..0..0..1....0..2..0....1..2..2....0..2..0....1..0..1....2..0..1....2..1..1
%e ..1..1..0....1..0..1....2..1..1....1..2..1....0..0..1....0..1..0....2..1..0
%Y Cf. A183792.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 07 2011