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

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