%I #5 Mar 31 2012 12:37:01
%S 2500,44641,752562,8183170,87487117,694547816,5466340007,34834605810,
%T 220710753856,1196535903414,6459574647599,30967790434185,
%U 148001428352179,644776741493252,2802681689033511,11319015179680230,45642521943090129
%N Number of (n+1)X4 0..2 arrays with the sums of 2X2 subblocks nondecreasing rightwards and downwards
%C Column 3 of A204230
%H R. H. Hardin, <a href="/A204225/b204225.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..0..2..0....2..1..0..0....0..0..2..0....1..1..2..0....2..1..0..2
%e ..0..0..2..0....0..0..2..1....0..0..0..1....1..0..0..1....0..0..2..0
%e ..0..1..1..1....1..2..2..1....1..0..2..1....0..2..1..1....1..2..0..2
%e ..0..1..2..2....1..1..2..2....0..2..2..2....2..0..2..2....1..2..2..2
%e ..1..0..2..1....2..2..2..1....0..1..2..1....1..2..1..1....2..2..1..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 13 2012