A205990 Number of (n+1)X(n+1) 0..2 arrays with the number of clockwise edge increases in every 2X2 subblock equal to two, and every 2X2 determinant nonzero

26, 498, 22612, 2437024, 619044912, 372736115952, 529835251171222, 1784953426699556450, 14217384542435576039962, 268389362522048765430516260, 11988698179720320887135239667414, 1269247322036771438138592002629758982

Offset

1,1

Comments

Diagonal of A205998

Links

Table of n, a(n) for n=1..12.

Example

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

Crossrefs

Sequence in context: A240190 A001723 A163201 * A230247 A058461 A323492

Adjacent sequences: A205987 A205988 A205989 * A205991 A205992 A205993

Keyword

nonn

Author

R. H. Hardin Feb 02 2012

Status

approved