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A147331 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 00100-00100-11111-00100 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 5, 21, 42, 179, 648, 2171, 10276, 78975, 494260 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.1.0.0.0

.0.0.1.1.1.1.1.0

.0.0.0.0.1.0.0.0

.0.0.0.0.1.0.0.0

.0.0.0.1.0.0.0.0

.0.0.0.1.0.0.0.0

.0.1.1.1.1.1.0.0

.0.0.0.1.0.0.0.0

CROSSREFS

Sequence in context: A146022 A054286 A031292 * A078371 A265056 A049741

Adjacent sequences:  A147328 A147329 A147330 * A147332 A147333 A147334

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved

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Last modified September 24 15:33 EDT 2021. Contains 347643 sequences. (Running on oeis4.)