A147272 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1000-1111-0001 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 13, 25, 49, 141, 407, 1043, 2925, 11783, 52869, 254667, 1211663

Offset

1,10

Links

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

Example

Maximal 10 X 10 example
.0.0.0.0.0.0.0.1.0.0
.0.0.0.0.1.1.1.1.0.0
.0.0.0.0.1.0.0.0.1.1
.0.0.0.0.1.0.0.0.1.0
.0.1.1.1.0.0.0.0.1.0
.0.1.0.0.0.0.1.1.1.0
.0.1.0.0.0.1.0.0.0.0
.1.1.0.0.0.1.0.0.0.0
.0.0.1.1.1.1.0.0.0.0
.0.0.1.0.0.0.0.0.0.0

Crossrefs

Sequence in context: A146192 A147265 A272705 * A147427 A147408 A241657

Adjacent sequences: A147269 A147270 A147271 * A147273 A147274 A147275

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved