A190659 - OEIS

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A190659

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

0

1, 1, 1, 3, 3, 8, 20, 53, 141, 552, 2419, 12788, 78700, 561036, 4750312

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

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

..0..0..0..0..0....0..0..0..1..1....0..0..1..1..1

..0..0..0..0..0....0..0..0..1..1....0..0..1..1..1

..0..0..0..0..0....0..0..0..1..1....1..1..0..0..0

..0..0..0..0..0....1..1..1..0..0....1..1..0..0..0

..0..0..0..0..0....1..1..1..0..0....1..1..0..0..0

CROSSREFS

Sequence in context: A049974 A049972 A027376 * A202536 A038068 A267952

Adjacent sequences: A190656 A190657 A190658 * A190660 A190661 A190662

KEYWORD

nonn

AUTHOR

R. H. Hardin May 16 2011

STATUS

approved