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A207437 Number of n X 3 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 0 vertically.

%I A207437 #8 Jun 22 2018 15:10:08
%S A207437 6,36,108,333,1144,4048,14743,54250,201098,747683,2785178,10383774,
%T A207437 38732585,144511028,539243500,2012324661,7509786472,28026278000,
%U A207437 104594259855,390348614698,1456795959866,5436826706395,20290493971290
%N A207437 Number of n X 3 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 0 vertically.
%C A207437 Column 3 of A207442.
%H A207437 R. H. Hardin, <a href="/A207437/b207437.txt">Table of n, a(n) for n = 1..210</a>
%F A207437 Empirical: a(n) = 6*a(n-1) - 5*a(n-2) - 22*a(n-3) + 32*a(n-4) + 16*a(n-5) - 35*a(n-6) + 2*a(n-7) + 9*a(n-8) - 2*a(n-9) for n>10.
%F A207437 Empirical g.f.: x*(6 - 78*x^2 - 3*x^3 + 286*x^4 - 23*x^5 - 321*x^6 + 64*x^7 + 87*x^8 - 22*x^9) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 - 4*x + x^2)*(1 + x - x^2)*(1 - x - x^2)). - _Colin Barker_, Jun 22 2018
%e A207437 Some solutions for n=4:
%e A207437 ..0..1..1....1..1..1....0..0..0....0..1..1....1..0..1....0..1..1....1..1..0
%e A207437 ..1..1..0....1..1..1....0..1..1....0..0..0....0..1..1....1..1..1....1..0..1
%e A207437 ..1..1..1....0..1..1....0..0..0....0..1..1....1..1..0....0..0..0....1..1..0
%e A207437 ..1..0..1....1..1..0....0..1..1....0..1..1....1..0..1....1..1..1....0..1..1
%Y A207437 Cf. A207442.
%K A207437 nonn
%O A207437 1,1
%A A207437 _R. H. Hardin_, Feb 17 2012