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%I #10 Jun 10 2018 17:56:24
%S 16,40,98,238,584,1432,3516,8622,21158,51894,127322,312310,766198,
%T 1879520,4610912,11311058,27748262,68070236,166988412,409647388,
%U 1004934200,2465259322,6047686542,14835930358,36394946602,89282603930
%N Number of (n+1) X 2 0..1 arrays with the number of rightwards and downwards edge increases in each 2 X 2 subblock differing from the number in all its horizontal and vertical neighbors.
%C Column 1 of A205072.
%H R. H. Hardin, <a href="/A205065/b205065.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-2) + 2*a(n-3) + 4*a(n-5) - 3*a(n-6) + 4*a(n-8) - 2*a(n-9) for n > 10.
%F Empirical g.f.: 2*x*(8 + 20*x + 9*x^2 + 3*x^3 + 7*x^4 - 9*x^5 + 4*x^6 + 11*x^7 - 4*x^8 + x^9) / (1 - 5*x^2 - 2*x^3 - 4*x^5 + 3*x^6 - 4*x^8 + 2*x^9). - _Colin Barker_, Jun 10 2018
%e Some solutions for n=4:
%e 1 0 0 1 0 1 1 1 1 1 0 0 1 0 0 0 1 1 0 0
%e 0 1 0 0 1 1 1 1 0 1 1 0 0 0 0 1 1 1 0 1
%e 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 0 0 1 0 0
%e 0 1 1 1 0 1 0 1 0 0 0 0 0 0 0 1 1 1 0 0
%e 0 0 0 1 0 0 0 0 1 1 1 1 0 1 0 0 1 1 0 1
%Y Cf. A205072.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 21 2012
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