A207404 - OEIS

%I #5 Mar 31 2012 12:37:17

%S 8,64,216,729,1782,4356,8910,18225,33210,60516,101598,170569,269276,

%T 425104,639612,962361,1393020,2016400,2827220,3964081,5411538,7387524,

%U 9858186,13155129,17213742,22524516,28974330,37271025,47228280,59845696

%N Number of 4Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 1 0 vertically

%C Row 4 of A207403

%H R. H. Hardin, <a href="/A207404/b207404.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +6*a(n-2) -14*a(n-3) -14*a(n-4) +42*a(n-5) +14*a(n-6) -70*a(n-7) +70*a(n-9) -14*a(n-10) -42*a(n-11) +14*a(n-12) +14*a(n-13) -6*a(n-14) -2*a(n-15) +a(n-16)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 17 2012