A147473 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-1111-0100-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 13, 23, 41, 61, 155, 415, 1323

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.0.0.1.1.0.0.1.0
.1.1.1.1.0.0.1.0
.0.0.1.0.1.1.1.1
.0.0.1.0.0.0.1.1
.1.1.0.0.0.1.0.0
.1.1.1.1.0.1.0.0
.0.1.0.0.1.1.1.1
.0.1.0.0.1.1.0.0

Crossrefs

Sequence in context: A018709 A121756 A178825 * A030431 A090146 A348559

Adjacent sequences: A147470 A147471 A147472 * A147474 A147475 A147476

Keyword

nonn

Author

R. H. Hardin

Status

approved