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A147018 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 01000-11111-00010 pattern in any orientation. 0
1, 1, 1, 1, 5, 9, 21, 35, 177, 589, 4235, 15969, 164553, 879607, 12456629, 97189937, 1947709409, 20669429409 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

Maximal 8 X 8 example

.0.1.0.0.0.0.1.0

.1.1.0.1.1.1.1.1

.0.1.0.0.1.0.0.0

.0.1.1.0.0.0.1.0

.0.1.0.0.0.1.1.0

.0.0.0.1.0.0.1.0

.1.1.1.1.1.0.1.1

.0.1.0.0.0.0.1.0

CROSSREFS

Sequence in context: A068481 A146827 A216414 * A081883 A049744 A000323

Adjacent sequences:  A147015 A147016 A147017 * A147019 A147020 A147021

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified April 16 00:47 EDT 2014. Contains 240534 sequences.