A147399 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1110-0111-0001 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 5, 5, 17, 17, 45, 45, 217, 217, 1729, 1729, 28581, 28581, 422837, 422837, 7769557, 7769557, 212491441, 212491441

Offset

1,9

Links

Table of n, a(n) for n=1..26.

Example

Maximal 9 X 9 example
.0.0.0.1.0.1.0.0.0
.0.1.1.1.0.1.1.1.0
.1.1.1.0.0.0.1.1.1
.1.0.0.0.0.0.0.0.1
.0.0.0.0.0.0.0.0.0
.1.0.0.0.0.0.0.0.1
.1.1.1.0.0.0.1.1.1
.0.1.1.1.0.1.1.1.0
.0.0.0.1.0.1.0.0.0

Crossrefs

Sequence in context: A146780 A146860 A146185 * A147195 A147045 A146065

Adjacent sequences: A147396 A147397 A147398 * A147400 A147401 A147402

Keyword

nonn

Author

R. H. Hardin

Status

approved