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%I #7 Jun 26 2022 20:32:54
%S 324,1296,3600,10000,22500,50625,99225,194481,345744,614656,1016064,
%T 1679616,2624400,4100625,6125625,9150625,13176900,18974736,26501904,
%U 37015056,50381604,68574961,91298025,121550625,158760000,207360000
%N Number of (n+2) X 4 binary arrays avoiding patterns 001 and 011 in rows and columns.
%C Column 2 of A202100.
%H R. H. Hardin, <a href="/A202094/b202094.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +6*a(n-2) -14*a(n-3) -14*a(n-4) +42*a(n-5) +14*a(n-6) -70*a(n-7) +70*a(n-9) -14*a(n-10) -42*a(n-11) +14*a(n-12) +14*a(n-13) -6*a(n-14) -2*a(n-15) +a(n-16).
%e Some solutions for n=7
%e ..1..1..1..1....1..1..1..1....1..1..0..1....1..1..0..1....1..1..1..1
%e ..1..1..1..1....1..1..0..1....1..1..1..0....1..1..0..1....1..1..1..0
%e ..0..1..0..1....1..1..1..1....1..1..0..0....0..1..0..0....0..1..0..1
%e ..1..1..1..0....0..1..0..1....1..1..1..0....1..1..0..0....1..1..0..0
%e ..0..1..0..0....1..1..0..1....1..1..0..0....0..0..0..0....0..1..0..0
%e ..0..0..0..0....0..1..0..1....1..1..0..0....1..1..0..0....1..1..0..0
%e ..0..1..0..0....1..1..0..0....1..1..0..0....0..0..0..0....0..1..0..0
%e ..0..0..0..0....0..0..0..0....0..1..0..0....0..1..0..0....0..1..0..0
%e ..0..1..0..0....0..1..0..0....0..1..0..0....0..0..0..0....0..0..0..0
%Y Cf. A202100.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 11 2011