A190658 Half the number of n X n symmetric binary matrices with no element unequal to a strict majority of its vertical, antidiagonal and horizontal neighbors

1, 1, 3, 8, 38, 252, 2107, 22478, 331824, 6625044, 173531500, 6026107049, 280634679581, 17440962165250, 1440182982082321, 158309818157320775, 23213155114911168104, 4535580909418217659991, 1179764335891702406715256

Offset

1,3

Links

R. H. Hardin, Table of n, a(n) for n = 1..24

Example

Some solutions for n=5 with a(1,1)=0
..0..0..1..1..1....0..0..1..0..0....0..0..0..1..1....0..0..1..1..1
..0..1..1..1..0....0..1..1..0..0....0..0..0..1..1....0..1..1..1..1
..1..1..1..0..0....1..1..1..1..1....0..0..1..1..1....1..1..1..1..1
..1..1..0..0..1....0..0..1..1..0....1..1..1..1..1....1..1..1..1..0
..1..0..0..1..1....0..0..1..0..0....1..1..1..1..1....1..1..1..0..0

Crossrefs

Sequence in context: A089066 A099030 A264657 * A366629 A106558 A065914

Adjacent sequences: A190655 A190656 A190657 * A190659 A190660 A190661

Keyword

nonn

Author

R. H. Hardin May 16 2011

Status

approved