A203370 - OEIS

%I #5 Mar 31 2012 12:36:56

%S 21,4998,636912,93584344,13204707603,1887519232797,268596415269518,

%T 38282460992672716,5453232104885876045,776953643188694040712,

%U 110689277453680961314489,15769820956322189825472915

%N Number of nX7 0..2 arrays with every 1 immediately preceded by 0 to the left or above, and every 2 immediately preceded by both a 1 and a 0

%C Column 7 of A203371

%H R. H. Hardin, <a href="/A203370/b203370.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=4

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

%e ..0..1..1..1..1..2..0....0..0..1..2..0..0..1....0..0..0..1..0..1..2

%e ..1..0..2..0..1..0..1....1..1..0..0..1..0..0....0..0..1..0..0..0..1

%e ..0..1..0..0..2..0..1....0..2..1..2..0..0..0....0..0..0..0..1..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Dec 31 2011