A147215 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-0111-0011 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 17, 41, 71, 215, 773, 2523, 9517, 44347, 255961, 1482711, 8989887, 64060215, 492775957, 4232478379

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.0.0.0.0.0.1.1.0
.1.0.0.1.1.1.0.0
.1.1.0.1.1.0.0.0
.0.1.1.0.0.1.1.0
.0.1.1.0.0.1.1.0
.0.0.0.1.1.0.1.1
.0.0.1.1.1.0.0.1
.0.1.1.0.0.0.0.0

Crossrefs

Sequence in context: A350052 A078655 A052279 * A126790 A089200 A332227

Adjacent sequences: A147212 A147213 A147214 * A147216 A147217 A147218

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved