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A190629 Half the number of n X n symmetric binary matrices with no element equal to a strict majority of its vertical, antidiagonal and horizontal neighbors 1
1, 1, 3, 15, 115, 1587, 33283, 1147868, 64664807, 5886944926, 868821662115, 207892029761070, 80727613405529244, 50826500691456029359, 51893686154530928512158, 85927150265759233982684320 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..20

EXAMPLE

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

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

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

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

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

CROSSREFS

Sequence in context: A082163 A331122 A342167 * A341647 A074596 A087806

Adjacent sequences:  A190626 A190627 A190628 * A190630 A190631 A190632

KEYWORD

nonn

AUTHOR

R. H. Hardin May 14 2011

STATUS

approved

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Last modified April 20 10:31 EDT 2021. Contains 343132 sequences. (Running on oeis4.)