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A146845 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1001-1111-1000 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 5, 13, 35, 61, 141, 427, 1351, 4209, 19211, 75163, 402147, 1986547, 12595631, 74795099, 557304499 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.1.1.1.0

.1.0.0.1.0.1.0.0

.1.1.1.1.0.1.0.0

.1.0.0.0.0.1.1.0

.0.1.1.0.0.0.0.1

.0.0.1.0.1.1.1.1

.0.0.1.0.1.0.0.1

.0.1.1.1.0.0.0.0

CROSSREFS

Sequence in context: A092647 A171262 A006561 * A192310 A167710 A229924

Adjacent sequences:  A146842 A146843 A146844 * A146846 A146847 A146848

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified December 1 16:44 EST 2021. Contains 349430 sequences. (Running on oeis4.)