A203560 Number of nX4 0..2 arrays with row sums equal and column sums equal.

3, 33, 177, 5673, 32613, 513903, 7343451, 185804265, 1849858773, 30348858003, 499616140191, 10882786433775, 141444270208647, 2412815237573445, 41425627536496497, 824284992576210537, 12447291755448613317

Offset: 1

Author

R. H. Hardin Jan 03 2012

Keywords

• nonn

Comments

Column 4 of A203564

Examples

			Some solutions for n=5
..1..0..2..1....0..1..2..1....1..1..1..1....2..1..1..0....2..0..0..2
..0..2..0..2....0..0..2..2....0..0..2..2....1..0..1..2....2..0..2..0
..0..2..2..0....1..0..1..2....1..2..1..0....2..1..0..1....1..1..1..1
..2..1..1..0....2..2..0..0....1..2..0..1....0..1..1..2....0..2..0..2
..2..0..0..2....2..2..0..0....2..0..1..1....0..2..2..0....0..2..2..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..39