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A147025 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 01000-11111-01000 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 3, 15, 21, 45, 77, 273, 569, 2606, 6661, 31883, 89951, 535540, 1839325, 13532589, 55467031, 467306429, 2229430591, 22257836225 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

Table of n, a(n) for n=1..25.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.0.0.1.0

.1.1.1.1.1.0.1.0

.0.0.0.1.0.0.1.0

.0.1.0.0.0.1.1.1

.1.1.1.0.0.0.1.0

.0.1.0.0.1.0.0.0

.0.1.0.1.1.1.1.1

.0.1.0.0.1.0.0.0

CROSSREFS

Sequence in context: A110172 A261274 A014493 * A147017 A171570 A076825

Adjacent sequences:  A147022 A147023 A147024 * A147026 A147027 A147028

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified October 26 14:28 EDT 2021. Contains 348267 sequences. (Running on oeis4.)