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A207364 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

%I A207364 #8 Jun 22 2018 06:18:21
%S A207364 9,81,252,784,1736,3844,7130,13225,21965,36481,56154,86436,125832,
%T A207364 183184,255516,356409,480585,648025,850080,1115136,1429824,1833316,
%U A207364 2305862,2900209,3588221,4439449,5414990,6604900,7956720,9585216,11421144
%N A207364 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 1 vertically.
%C A207364 Column 4 of A207368.
%H A207364 R. H. Hardin, <a href="/A207364/b207364.txt">Table of n, a(n) for n = 1..210</a>
%F A207364 Empirical: a(n) = 2*a(n-1) + 4*a(n-2) - 10*a(n-3) - 5*a(n-4) + 20*a(n-5) - 20*a(n-7) + 5*a(n-8) + 10*a(n-9) - 4*a(n-10) - 2*a(n-11) + a(n-12).
%F A207364 Empirical g.f.: x*(9 + 63*x + 54*x^2 + 46*x^3 + 15*x^4 - 19*x^5 - 22*x^6 + 9*x^7 + 10*x^8 - 4*x^9 - 2*x^10 + x^11) / ((1 - x)^7*(1 + x)^5). - _Colin Barker_, Jun 22 2018
%e A207364 Some solutions for n=4:
%e A207364 ..1..0..0..1....0..0..1..0....1..1..1..1....1..1..0..1....0..1..0..0
%e A207364 ..0..1..0..1....1..1..0..0....1..1..1..1....1..1..0..1....1..1..0..1
%e A207364 ..1..0..0..1....0..0..1..0....1..1..1..1....0..1..0..0....0..1..0..0
%e A207364 ..0..1..0..1....1..1..0..0....0..1..0..1....0..1..0..0....1..1..0..0
%Y A207364 Cf. A207368.
%K A207364 nonn
%O A207364 1,1
%A A207364 _R. H. Hardin_, Feb 17 2012