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A146670 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-0110 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 3, 9, 19, 33, 71, 215, 791, 3245, 13621, 57411, 277797, 1527109, 9994857, 71286549, 571498723 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.1.1.0.0

.0.0.1.1.1.0.0.0

.0.1.0.1.1.0.0.1

.0.1.1.0.0.1.1.1

.1.1.1.0.0.1.1.0

.1.0.0.1.1.0.1.0

.0.0.0.1.1.1.0.0

.0.0.1.1.0.0.0.0

CROSSREFS

Sequence in context: A146702 A146734 A146614 * A146409 A147111 A146401

Adjacent sequences:  A146667 A146668 A146669 * A146671 A146672 A146673

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.)