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A190420 Number of (n+2)X(n+2) symmetric binary matrices without the pattern 1 1 1 diagonally or antidiagonally 1
44, 363, 6072, 191360, 10093200, 935338785, 154543989072, 44556415740672, 22668584136931568, 20377347136466565883, 32182451728510291871740, 89502269428191719999392640, 438593646987789744491801743584 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..17

EXAMPLE

Some solutions for n=2

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

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

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

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

CROSSREFS

Sequence in context: A183633 A200450 A024304 * A228464 A190605 A264555

Adjacent sequences:  A190417 A190418 A190419 * A190421 A190422 A190423

KEYWORD

nonn

AUTHOR

R. H. Hardin May 10 2011

STATUS

approved

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Last modified October 5 06:51 EDT 2022. Contains 357252 sequences. (Running on oeis4.)