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A146921 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0110-1111-0110 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 2, 4, 7, 11, 16, 35, 94, 264, 702, 1734, 4891, 17066, 67788, 281343, 1140052, 4839734, 23096235, 127115296, 766176694, 4824195749, 31420497455, 220872571333, 1715777826329 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

Table of n, a(n) for n=1..30.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.1.0.0.0

.0.0.1.1.1.1.0.0

.0.1.0.1.1.0.1.0

.1.1.1.0.0.1.1.1

.1.1.1.0.0.1.1.1

.0.1.0.1.1.0.1.0

.0.0.1.1.1.1.0.0

.0.0.0.1.1.0.0.0

CROSSREFS

Sequence in context: A120118 A108895 A146929 * A153535 A116615 A053145

Adjacent sequences:  A146918 A146919 A146920 * A146922 A146923 A146924

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified July 2 21:48 EDT 2022. Contains 355029 sequences. (Running on oeis4.)