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%I #5 Mar 31 2012 12:36:06
%S 1910,29020,440505,6687805,101532811,1541462868,23402344941,
%T 355292192013,5394012633636,81891392695720,1243267423038501,
%U 18875169103575908,286561042384512461,4350542798392582750,66049531656898579770
%N Half the number of (n+2)X4 binary arrays with each 3X3 subblock having a sum in 2..7
%C Column 2 of A186796
%H R. H. Hardin, <a href="/A186789/b186789.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n)=13*a(n-1)+27*a(n-2)+97*a(n-3)-13*a(n-4)-696*a(n-5)-487*a(n-6)+531*a(n-7)+1379*a(n-8)+420*a(n-9)-720*a(n-10)-888*a(n-11)-72*a(n-12)+216*a(n-13)+216*a(n-14)
%e Some solutions for 6X4 with a(1,1)=0
%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%e ..0..0..0..1....0..0..1..0....0..0..1..0....0..0..0..1....0..0..0..1
%e ..1..1..1..1....1..0..1..1....0..0..1..1....1..0..1..1....1..1..0..0
%e ..0..1..1..0....0..1..1..0....0..1..1..0....0..0..1..0....1..0..1..0
%e ..1..1..0..1....0..1..1..0....0..0..1..1....1..1..1..0....0..1..1..1
%e ..1..0..0..1....1..0..1..0....0..0..1..1....0..1..0..1....0..0..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 26 2011
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