A147007 - OEIS

A147007

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 00100-11111-00100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 6, 9, 14, 23, 57, 131, 385, 909, 2527, 6618, 23479

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OFFSET

1,9

LINKS

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

EXAMPLE

Maximal 9 X 9 example

.0.0.0.0.1.0.0.0.0

.0.0.1.1.1.1.1.0.0

.0.1.0.0.1.0.0.1.0

.0.1.0.0.0.0.0.1.0

.1.1.1.0.0.0.1.1.1

.0.1.0.0.0.0.0.1.0

.0.1.0.0.1.0.0.1.0

.0.0.1.1.1.1.1.0.0

.0.0.0.0.1.0.0.0.0

CROSSREFS

Sequence in context: A228364 A018060 A115856 * A146937 A032231 A200273

Adjacent sequences: A147004 A147005 A147006 * A147008 A147009 A147010

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved