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%I #11 Sep 30 2018 02:44:49
%S 2,6,20,57,164,485,1424,4169,12228,35868,105177,308433,904520,2652574,
%T 7778858,22812126,66898367,196184665,575326896,1687191264,4947820577,
%U 14509871545,42551335553,124785126404,365942162811,1073154072467
%N Number of n X 2 0..1 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors.
%H R. H. Hardin, <a href="/A231538/b231538.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) - 4*a(n-2) + 5*a(n-3) - 8*a(n-4) + 3*a(n-5) - 2*a(n-6) + a(n-7) - a(n-8).
%F Empirical g.f.: x*(2 - 2*x + 4*x^2 - 9*x^3 + 2*x^4 - x^5 + x^6 - x^7) / (1 - 4*x + 4*x^2 - 5*x^3 + 8*x^4 - 3*x^5 + 2*x^6 - x^7 + x^8). - _Colin Barker_, Sep 29 2018
%e Some solutions for n=7:
%e 0 1 1 0 1 1 0 1 1 1 1 0 0 1 0 0 0 0 1 0
%e 0 1 0 0 1 1 0 0 0 0 0 0 0 1 0 0 1 0 0 0
%e 0 0 0 1 0 0 1 0 0 0 0 1 0 1 0 0 0 0 1 1
%e 1 0 0 0 0 0 0 0 1 1 1 1 0 0 1 0 1 1 1 0
%e 0 1 0 1 1 0 0 1 1 1 1 1 1 0 1 0 1 1 0 0
%e 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0
%e 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 1 0 0 0 0
%Y Column 2 of A231544.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 10 2013