A147098 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1000-1000-1111 pattern in any orientation.

1, 1, 1, 1, 3, 7, 13, 29, 143, 539, 2419, 11799, 70509, 422003, 3669313, 30560805, 384390343

Offset

1,5

Links

Table of n, a(n) for n=1..17.

Example

Maximal 8 X 8 example
.0.0.1.1.1.1.0.0
.0.0.0.0.0.1.0.0
.1.1.1.1.0.1.0.1
.1.0.0.0.0.1.0.1
.1.0.1.0.0.0.0.1
.1.0.1.0.1.1.1.1
.0.0.1.0.0.0.0.0
.0.0.1.1.1.1.0.0

Crossrefs

Sequence in context: A134270 A091565 A025249 * A109291 A340067 A199218

Adjacent sequences: A147095 A147096 A147097 * A147099 A147100 A147101

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved