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A207021 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

%I A207021 #10 Jul 22 2025 19:57:08
%S A207021 13,169,624,1586,3315,6123,10374,16484,24921,36205,50908,69654,93119,
%T A207021 122031,157170,199368,249509,308529,377416,457210,549003,653939,
%U A207021 773214,908076,1059825,1229813,1419444,1630174,1863511,2121015,2404298,2715024
%N A207021 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.
%C A207021 Column 5 of A207024
%H A207021 R. H. Hardin, <a href="/A207021/b207021.txt">Table of n, a(n) for n = 1..210</a>
%F A207021 Empirical: a(n) = (13/6)*n^4 + 13*n^3 + (52/3)*n^2 - (39/2)*n.
%F A207021 Empirical G.f.: 13*x*(1+8*x-7*x^2+2*x^3)/(1-x)^5. [_Colin Barker_, May 22 2012]
%e A207021 Some solutions for n=4
%e A207021 ..1..0..1..0..0....0..0..1..0..0....1..1..1..1..1....0..0..1..0..1
%e A207021 ..0..1..0..0..1....0..0..1..0..0....1..1..1..0..1....1..1..0..1..0
%e A207021 ..0..1..0..0..1....0..0..1..0..0....0..1..0..0..1....0..1..0..1..0
%e A207021 ..0..1..0..0..1....0..0..1..0..0....0..1..0..0..1....0..1..0..1..0
%K A207021 nonn
%O A207021 1,1
%A A207021 _R. H. Hardin_ Feb 14 2012