A204225 Number of (n+1)X4 0..2 arrays with the sums of 2X2 subblocks nondecreasing rightwards and downwards.

2500, 44641, 752562, 8183170, 87487117, 694547816, 5466340007, 34834605810, 220710753856, 1196535903414, 6459574647599, 30967790434185, 148001428352179, 644776741493252, 2802681689033511, 11319015179680230, 45642521943090129

Offset: 1

Author

R. H. Hardin Jan 13 2012

Keywords

• nonn

Comments

Column 3 of A204230

Examples

			Some solutions for n=4
..0..0..2..0....2..1..0..0....0..0..2..0....1..1..2..0....2..1..0..2
..0..0..2..0....0..0..2..1....0..0..0..1....1..0..0..1....0..0..2..0
..0..1..1..1....1..2..2..1....1..0..2..1....0..2..1..1....1..2..0..2
..0..1..2..2....1..1..2..2....0..2..2..2....2..0..2..2....1..2..2..2
..1..0..2..1....2..2..2..1....0..1..2..1....1..2..1..1....2..2..1..2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210