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%I #4 Jun 15 2013 14:08:49
%S 9,71,427,2393,13691,80043,469273,2739433,15958607,93008549,542420159,
%T 3163594535,18448581619,107577118339,627315001045,3658138216921,
%U 21332152588333,124396206594399,725402407325709,4230105619473679
%N Number of nX2 (-1,0,1) arrays of determinants of 2X2 subblocks of some (n+1)X3 binary array
%C Column 2 of A226717
%H R. H. Hardin, <a href="/A226711/b226711.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +4*a(n-2) +43*a(n-3) +198*a(n-4) +625*a(n-5) +1567*a(n-6) +3202*a(n-7) +5151*a(n-8) +6414*a(n-9) +6021*a(n-10) +4065*a(n-11) +1737*a(n-12) +216*a(n-13) -252*a(n-14) -168*a(n-15) -36*a(n-16)
%e Some solutions for n=3
%e .-1..0....0..1...-1..0....1.-1...-1..1....1..0...-1..0....0.-1....0..0....1..0
%e ..0..0...-1..0....0.-1...-1..0....1.-1...-1..0....1..0....1..1....1..1....0..0
%e .-1..0...-1..0....1..1....0.-1....0..1....0.-1....1..1....0..0....0..1...-1.-1
%K nonn
%O 1,1
%A _R. H. Hardin_ Jun 15 2013
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