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A147021 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 01000-11111-01000 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 33, 13, 357, 57, 3654, 277, 39873, 2427, 687008, 27961, 15511627, 440433, 608333563, 11044775, 33683651469, 365499077 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,11

LINKS

Table of n, a(n) for n=1..26.

EXAMPLE

Maximal 11 X 11 example

.0.0.0.1.0.0.0.1.0.0.0

.1.1.1.1.1.0.1.1.1.1.1

.0.0.0.1.0.0.0.1.0.0.0

.0.0.0.0.0.0.0.0.0.0.0

.0.0.0.1.0.0.0.1.0.0.0

.1.1.1.1.1.0.1.1.1.1.1

.0.0.0.1.0.0.0.1.0.0.0

.0.0.0.0.0.0.0.0.0.0.0

.0.0.0.1.0.0.0.1.0.0.0

.1.1.1.1.1.0.1.1.1.1.1

.0.0.0.1.0.0.0.1.0.0.0

CROSSREFS

Sequence in context: A120584 A236177 A123173 * A200897 A138839 A033353

Adjacent sequences:  A147018 A147019 A147020 * A147022 A147023 A147024

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified January 16 00:05 EST 2021. Contains 340195 sequences. (Running on oeis4.)