A190630 Half the number of n X n symmetric binary matrices with no element equal to a strict majority of its knight-move neighbors

1, 4, 6, 8, 63, 563, 10027, 209836, 6257561, 259705792

Offset

1,2

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for n=4 with a(1,1)=0
..0..1..0..0....0..0..1..0....0..0..1..1....0..1..0..0....0..0..1..1
..1..0..1..0....0..1..1..1....0..0..1..1....1..1..1..0....0..0..1..1
..0..1..1..1....1..1..1..0....1..1..0..0....0..1..1..1....1..1..1..0
..0..0..1..0....0..1..0..0....1..1..0..0....0..0..1..0....1..1..0..0

Crossrefs

Sequence in context: A087271 A067797 A203633 * A013285 A013289 A013288

Adjacent sequences: A190627 A190628 A190629 * A190631 A190632 A190633

Keyword

nonn

Author

R. H. Hardin May 14 2011

Status

approved