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%I #9 Sep 14 2018 16:12:37
%S 8,38,184,869,4144,19675,93589,444824,2114934,10054148,47798953,
%T 227238276,1080310539,5135871337,24416324712,116077006646,
%U 551838764656,2623482504621,12472231233800,59293915534091,281887688707501
%N Number of n X 2 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 antidiagonally.
%H R. H. Hardin, <a href="/A229366/b229366.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 13*a(n-2) + 3*a(n-3) - 13*a(n-4) + 4*a(n-5).
%F Empirical g.f.: x*(8 + 22*x + 4*x^2 - 17*x^3 + 4*x^4) / (1 - 2*x - 13*x^2 - 3*x^3 + 13*x^4 - 4*x^5). - _Colin Barker_, Sep 14 2018
%e Some solutions for n=4:
%e 1 0 0 0 0 2 2 1 2 1 1 0 2 1 0 1 0 1 0 2
%e 1 0 1 0 0 0 0 2 0 1 1 0 0 0 1 2 0 2 2 0
%e 1 0 1 2 1 0 0 0 0 0 2 0 2 0 1 0 1 0 1 0
%e 1 0 2 0 2 0 1 2 2 0 1 2 1 0 2 2 1 2 2 0
%Y Column 2 of A229372.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 21 2013
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