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A208122 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.

%I A208122 #7 Jul 22 2025 21:11:01
%S A208122 20,400,1260,3969,34713,303601,1432600,6760000,45648200,308248249,
%T A208122 1680152229,9157915809,56635398540,350250912400,2009057864020,
%U A208122 11524062773521,69120684953057,414582008296369,2421339816495600
%N A208122 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.
%C A208122 Row 7 of A208118
%H A208122 R. H. Hardin, <a href="/A208122/b208122.txt">Table of n, a(n) for n = 1..210</a>
%F A208122 Empirical: a(n) = a(n-1) -12*a(n-2) +55*a(n-3) +805*a(n-4) +900*a(n-5) +10320*a(n-6) -123840*a(n-8) -129600*a(n-9) -1391040*a(n-10) -1140480*a(n-11) +2985984*a(n-12) -2985984*a(n-13) +35831808*a(n-14)
%e A208122 Some solutions for n=4
%e A208122 ..0..0..1..1....0..0..1..1....0..0..1..1....1..1..1..1....1..1..0..0
%e A208122 ..1..0..1..1....1..0..0..1....1..1..1..1....0..1..1..1....0..0..1..1
%e A208122 ..0..0..1..1....0..0..1..1....0..0..1..1....0..1..1..1....1..1..0..0
%e A208122 ..1..0..1..1....1..0..0..1....1..1..0..0....0..0..1..1....0..0..1..1
%e A208122 ..0..0..1..1....0..0..1..1....0..0..1..1....0..1..1..0....1..1..0..0
%e A208122 ..1..0..0..1....1..0..0..1....1..1..0..0....0..0..1..1....0..0..1..1
%e A208122 ..0..0..1..1....0..0..1..1....0..0..1..1....0..1..1..0....1..1..0..0
%K A208122 nonn
%O A208122 1,1
%A A208122 _R. H. Hardin_ Feb 23 2012