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A228384 Number of n X n binary arrays with top left value 1 and no two ones adjacent horizontally or vertically. 1
1, 2, 21, 382, 17578, 1755243, 402968942, 207573951234, 242284444195349, 638096588519781536, 3798652903378388363280, 51076133156779686951912785, 1551660182965034835583479000348, 106488245934766828340647881986248382 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Diagonal of A228390

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..30

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A177234 A099710 A098344 * A216281 A263625 A245686

Adjacent sequences:  A228381 A228382 A228383 * A228385 A228386 A228387

KEYWORD

nonn

AUTHOR

R. H. Hardin Aug 21 2013

STATUS

approved

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Last modified February 24 22:57 EST 2020. Contains 332216 sequences. (Running on oeis4.)