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%I #12 Mar 09 2018 10:54:46
%S 35,1225,7210,24990,65765,145775,287140,518700,876855,1406405,2161390,
%T 3205930,4615065,6475595,8886920,11961880,15827595,20626305,26516210,
%U 33672310,42287245,52572135,64757420,79093700,95852575,115327485
%N Number of n X 7 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically.
%C Column 7 of A209650.
%H R. H. Hardin, <a href="/A209649/b209649.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*n^5 + 70*n^4 + (35/3)*n^3 - (105/2)*n^2 - (7/6)*n.
%F Conjectures from _Colin Barker_, Mar 07 2018: (Start)
%F G.f.: 35*x*(1 + x)*(1 + 28*x - 17*x^2) / (1 - x)^6.
%F a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
%F (End)
%e Some solutions for n=4:
%e 1 0 1 0 1 0 1 0 1 0 1 1 1 0 1 1 0 1 1 0 1
%e 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
%e 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
%e 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
%Y Cf. A209650.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 11 2012
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