A228679 - OEIS

%I #9 Sep 02 2013 13:01:06

%S 8,40,216,1152,6160,32928,176032,941056,5030848,26894720,143778176,

%T 768632832,4109082880,21967006208,117434808832,627802177536,

%U 3356207397888,17942161561600,95918137153536,512774840614912

%N Number of nX4 binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally.

%C Column 4 of A228683

%H R. H. Hardin, <a href="/A228679/b228679.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) -2*a(n-2) -8*a(n-3).

%F Empirical: G.f. -8*x*(-1+x+x^2) / ( 1-6*x+2*x^2+8*x^3 ). - _R. J. Mathar_, Aug 31 2013

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Aug 30 2013