A147282 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1100-0111-0001 pattern in any orientation.

1, 1, 1, 1, 1, 9, 29, 121, 541, 3221, 21119, 159497, 1485397, 18836335, 303422599, 5770504647

Offset

1,6

Links

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

Example

Maximal 8 X 8 example
.0.0.0.0.1.0.0.0
.1.1.0.0.1.1.1.0
.0.1.1.0.0.0.1.1
.0.0.1.0.1.1.0.1
.1.0.1.1.0.1.0.0
.1.1.0.0.0.1.1.0
.0.1.1.1.0.0.1.1
.0.0.0.1.0.0.0.0

Crossrefs

Sequence in context: A183245 A101141 A056258 * A146602 A146413 A146054

Adjacent sequences: A147279 A147280 A147281 * A147283 A147284 A147285

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved