A187404 Number of (n+1)X(n+1) 0..4 arrays with diagonal zero and the i,j-th 2X2 subblock sum equal to the j,i-th 2X2 subblock sum.

25, 1751, 426425, 397056235, 1500716036725, 24045057041759375, 1689575552125034440625

Offset

1,1

Comments

Column 4 of A187408

Links

Table of n, a(n) for n=1..7.

Example

Some solutions for 4X4
..0..0..1..2....0..0..3..0....0..0..2..2....0..0..4..0....0..1..1..1
..3..0..4..2....0..0..2..1....0..0..2..0....4..0..3..1....2..0..4..4
..0..2..0..0....4..1..0..0....2..2..0..2....0..3..0..1....3..1..0..0
..4..3..1..0....0..1..1..0....2..0..2..0....3..2..0..0....2..4..3..0

Crossrefs

Sequence in context: A290881 A316911 A212333 * A370436 A172261 A023113

Adjacent sequences: A187401 A187402 A187403 * A187405 A187406 A187407

Keyword

nonn

Author

R. H. Hardin, Mar 09 2011

Status

approved