A202681 Number of n X 3 0..3 arrays with row sums equal and column sums equal.

4, 16, 340, 832, 6784, 224764, 496276, 4373632, 231072928, 353406676, 3224421556, 280342927660, 274352334052, 2553096089392, 372538530340720, 224184063052672, 2113024132266112, 524189682100412404, 189520876535392852

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..67

Example

Some solutions for n=3
..0..2..3....0..1..1....2..3..0....2..1..2....3..2..0....2..0..2....2..2..2
..3..0..2....2..0..0....0..2..3....1..1..3....0..2..3....2..2..0....1..3..2
..2..3..0....0..1..1....3..0..2....2..3..0....2..1..2....0..2..2....3..1..2

Crossrefs

Column 3 of A202686.

Sequence in context: A014731 A023114 A207851 * A067211 A156337 A000874

Adjacent sequences: A202678 A202679 A202680 * A202682 A202683 A202684

Keyword

nonn

Author

R. H. Hardin, Dec 22 2011

Status

approved