A147183 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1111-0101 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 13, 37, 69, 153, 515, 1541, 5473, 24829, 107075, 576645, 3229459, 20010951, 136930705, 1005926097

Offset

1,7

Links

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

Example

Maximal 8 X 8 example
.0.0.0.0.1.1.0.0
.0.1.0.1.0.1.1.0
.1.1.1.1.0.1.0.0
.1.0.0.0.0.1.1.0
.0.1.1.0.0.0.0.1
.0.0.1.0.1.1.1.1
.0.1.1.0.1.0.1.0
.0.0.1.1.0.0.0.0

Crossrefs

Sequence in context: A107136 A153009 A147168 * A254955 A098547 A256316

Adjacent sequences: A147180 A147181 A147182 * A147184 A147185 A147186

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved