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A190342 Number of (n+1)X(n+1) symmetric binary matrices without the pattern 1 1 vertically, antidiagonally or horizontally 1
4, 12, 52, 308, 2520, 29268, 471012, 10566004, 331575100, 14510475976, 885694047808, 75478844279780, 8975435807171244, 1489232331953993836, 344849471434261285096, 111434896145450843664604 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..39

EXAMPLE

Some solutions for 3X3

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

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

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

CROSSREFS

Sequence in context: A277431 A065525 A317281 * A262745 A180381 A149413

Adjacent sequences:  A190339 A190340 A190341 * A190343 A190344 A190345

KEYWORD

nonn

AUTHOR

R. H. Hardin May 09 2011

STATUS

approved

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Last modified December 3 19:39 EST 2021. Contains 349468 sequences. (Running on oeis4.)