A203559 Number of nX3 0..2 arrays with row sums equal and column sums equal.

3, 9, 87, 177, 993, 10833, 35619, 219873, 2083713, 8710539, 55644339, 473819481, 2320792659, 15120204297, 119105713827, 650725327233, 4293779332929, 32065818855387, 188739799967427, 1256510215733187, 9061494550445907

Offset

1,1

Comments

Column 3 of A203564

Links

R. H. Hardin, Table of n, a(n) for n = 1..122

Example

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

Crossrefs

Sequence in context: A032078 A307799 A326159 * A184098 A249789 A067210

Adjacent sequences: A203556 A203557 A203558 * A203560 A203561 A203562

Keyword

nonn

Author

R. H. Hardin, Jan 03 2012

Status

approved