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A208165 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 0 1 0 vertically.

%I A208165 #7 Jul 22 2025 21:12:54
%S A208165 9,81,287,981,2920,9039,28681,89623,278652,872602,2730176,8525256,
%T A208165 26645271,83307020,260355204,813693708,2543369350,7949447810,
%U A208165 24845860649,77657127110,242721701342,758634528231,2371142647768,7411113488204
%N A208165 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 0 1 0 vertically.
%C A208165 Row 4 of A208164
%H A208165 R. H. Hardin, <a href="/A208165/b208165.txt">Table of n, a(n) for n = 1..210</a>
%F A208165 Empirical: a(n) = a(n-1) +16*a(n-3) +13*a(n-4) +21*a(n-5) -24*a(n-6) -56*a(n-7) -65*a(n-8) +3*a(n-9) +93*a(n-10) +114*a(n-11) +a(n-12) -99*a(n-13) -107*a(n-14) +14*a(n-15) +86*a(n-16) +39*a(n-17) -34*a(n-18) -19*a(n-19) +6*a(n-21) for n>23
%e A208165 Some solutions for n=4
%e A208165 ..1..1..0..0....1..1..1..1....0..1..1..1....0..1..1..0....0..1..1..0
%e A208165 ..0..0..1..0....1..0..0..1....1..0..0..1....0..0..1..1....0..1..0..0
%e A208165 ..0..1..1..0....1..1..1..1....1..0..0..1....0..1..1..1....0..0..1..0
%e A208165 ..0..1..1..0....0..1..1..1....1..0..0..1....0..1..1..0....0..1..1..0
%K A208165 nonn
%O A208165 1,1
%A A208165 _R. H. Hardin_ Feb 24 2012