A183812 1/81 the number of (n+1)X(n+1) 0..2 arrays with no 2X2 subblock being a reflection across the shared element pair of any horizontal or vertical neighbor

1, 162, 163208, 1042063656, 41531687999736, 10425296660739253420

Offset

1,2

Comments

Diagonal of A183819

Links

Table of n, a(n) for n=1..6.

Example

Some solutions with upper left block zero for 3X3
..0..0..2....0..0..0....0..0..2....0..0..0....0..0..2....0..0..0....0..0..0
..0..0..0....0..0..1....0..0..1....0..0..2....0..0..2....0..0..1....0..0..1
..2..2..0....0..1..2....1..1..1....1..1..1....1..2..1....2..0..1....1..2..1

Crossrefs

Sequence in context: A291131 A209965 A230837 * A036914 A325063 A214185

Adjacent sequences: A183809 A183810 A183811 * A183813 A183814 A183815

Keyword

nonn

Author

R. H. Hardin Jan 07 2011

Status

approved