A147216 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-0111-0011 pattern in any orientation.

1, 1, 1, 1, 5, 21, 61, 299, 1693, 11273, 84165, 889613, 11762051, 208288599, 4127254537, 109970171123

Offset

1,5

Links

Table of n, a(n) for n=1..16.

Example

Maximal 8 X 8 example
.0.0.0.0.0.1.1.0
.0.0.0.1.1.1.0.1
.0.0.0.1.1.0.1.1
.0.1.1.0.0.1.1.0
.0.1.1.0.0.1.1.0
.1.1.0.1.1.0.0.0
.1.0.1.1.1.0.0.0
.0.1.1.0.0.0.0.0

Crossrefs

Sequence in context: A147375 A351934 A356328 * A362573 A196631 A357723

Adjacent sequences: A147213 A147214 A147215 * A147217 A147218 A147219

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved