A147212 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1100-0111-0011 pattern in any orientation.

1, 1, 1, 1, 3, 9, 23, 55, 315, 2117, 14227, 107639, 1242577, 18337443, 306941589, 6236872411, 166949397689, 5617277183949, 229023263912585, 11581498844555427

Offset

1,5

Links

Table of n, a(n) for n=1..20.

Example

Maximal 8 X 8 example
.0.0.0.0.1.1.0.0
.0.0.0.0.0.1.1.1
.0.0.0.0.0.0.1.1
.0.0.0.0.1.1.0.0
.1.0.0.1.0.1.1.1
.1.1.0.1.1.0.1.1
.0.1.1.0.1.1.0.0
.0.1.1.0.1.1.0.0

Crossrefs

Sequence in context: A305168 A274099 A147126 * A341029 A045883 A292329

Adjacent sequences: A147209 A147210 A147211 * A147213 A147214 A147215

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved