A147396 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1000-1000-1111-0001-0001 pattern in any orientation.

1, 1, 1, 1, 1, 1, 5, 13, 45, 145, 549, 1997, 9119, 41645

Offset

1,7

Links

Table of n, a(n) for n=1..14.

Example

Maximal 8 X 8 example
.0.0.0.1.1.1.0.0
.0.0.0.0.0.1.0.0
.0.0.0.0.0.1.0.0
.0.0.0.0.0.1.1.1
.1.1.1.0.0.0.0.0
.0.0.1.0.0.0.0.0
.0.0.1.0.0.0.0.0
.0.0.1.1.1.0.0.0

Crossrefs

Sequence in context: A322203 A052899 A147200 * A320877 A099972 A060050

Adjacent sequences: A147393 A147394 A147395 * A147397 A147398 A147399

Keyword

nonn

Author

R. H. Hardin

Status

approved