A206878 - OEIS

%I #5 Mar 31 2012 12:37:14

%S 7,49,230,1011,4705,22412,105936,497727,2339729,11013295,51846666,

%T 244013222,1148355280,5404522372,25435928407,119711433603,

%U 563405871570,2651594982047,12479394172896,58732688555813,276417903263710

%N Number of nX3 0..1 arrays avoiding 0 1 0 horizontally and 1 0 1 vertically

%C Column 3 of A206883

%H R. H. Hardin, <a href="/A206878/b206878.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) -7*a(n-2) +24*a(n-3) +8*a(n-4) +11*a(n-5) +32*a(n-6) -22*a(n-7) -44*a(n-8) +11*a(n-9) +13*a(n-10) -a(n-11) -a(n-12)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 13 2012