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Number of n X 6 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 0 1 vertically.
1

%I #8 Jun 20 2018 08:29:23

%S 19,361,1482,3952,8455,15789,26866,42712,64467,93385,130834,178296,

%T 237367,309757,397290,501904,625651,770697,939322,1133920,1356999,

%U 1611181,1899202,2223912,2588275,2995369,3448386,3950632,4505527,5116605

%N Number of n X 6 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 0 1 vertically.

%C Column 6 of A207169.

%H R. H. Hardin, <a href="/A207167/b207167.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (19/4)*n^4 + (95/2)*n^3 - (57/4)*n^2 - 19*n.

%F Conjectures from _Colin Barker_, Jun 20 2018: (Start)

%F G.f.: 19*x*(1 + 14*x - 7*x^2 - 2*x^3) / (1 - x)^5.

%F a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.

%F (End)

%e Some solutions for n=4:

%e ..1..1..1..1..0..0....1..0..0..1..0..0....1..0..0..1..0..0....1..0..0..1..0..0

%e ..0..0..1..0..0..1....0..1..1..0..0..1....1..1..1..0..0..1....0..1..1..0..0..1

%e ..0..0..1..0..0..1....0..0..1..0..0..1....0..0..1..0..0..1....0..1..1..0..0..1

%e ..0..0..1..0..0..1....0..0..1..0..0..1....0..0..1..0..0..1....0..0..1..0..0..1

%Y Cf. A207169.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 15 2012