A147337 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 01000-11100-00111-00010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 9, 21, 61, 255, 1001, 4645, 25381, 168687, 1415389

Offset

1,7

Links

Table of n, a(n) for n=1..15.

Example

Maximal 8 X 8 example
.0.0.0.0.0.0.1.0
.0.0.0.0.0.0.1.1
.0.0.0.0.0.1.1.0
.0.0.1.0.1.1.0.0
.0.0.1.1.0.1.0.0
.0.1.1.0.0.0.0.0
.1.1.0.0.0.0.0.0
.0.1.0.0.0.0.0.0

Crossrefs

Sequence in context: A246327 A320896 A127989 * A020290 A020288 A338007

Adjacent sequences: A147334 A147335 A147336 * A147338 A147339 A147340

Keyword

nonn,more

Author

R. H. Hardin

Status

approved