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%I #8 Jun 14 2018 08:05:44
%S 45,130,336,992,2996,9072,27656,84152,256416,781232,2379776,7251312,
%T 22090736,67305392,205057296,624739472,1903397456,5799009552,
%U 17667779216,53828031632,163996770576,499645981712,1522260939536,4637843595792
%N Number of (n+1) X 3 0..2 arrays with every 2 X 3 or 3 X 2 subblock having exactly two equal edges, and new values 0..2 introduced in row major order.
%C Column 2 of A206215.
%H R. H. Hardin, <a href="/A206209/b206209.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 6*a(n-2) + 4*a(n-3) - 10*a(n-4) for n>6.
%F Empirical g.f.: x*(45 + 85*x - 64*x^2 - 304*x^3 - 82*x^4 + 80*x^5) / ((1 - x)*(1 - 6*x^2 - 10*x^3)). - _Colin Barker_, Jun 14 2018
%e Some solutions for n=4:
%e ..0..0..0....0..1..2....0..1..1....0..1..0....0..0..1....0..1..1....0..1..2
%e ..1..2..1....0..0..1....0..2..0....2..0..0....0..2..0....1..2..1....0..0..1
%e ..1..0..1....1..0..0....0..1..0....0..0..1....2..0..0....1..1..2....1..0..0
%e ..1..2..1....0..2..0....0..2..0....0..1..2....0..0..2....2..1..1....2..1..1
%e ..0..0..0....0..0..1....0..1..0....1..2..2....0..2..1....1..2..2....1..1..2
%Y Cf. A206215.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 04 2012
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