A147503 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1110-0110-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 7, 19, 33, 55, 139, 371, 947, 2907, 11335

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.1.0.0.0.0.1.1.1
.1.1.1.0.0.1.1.0
.1.1.1.0.1.1.1.0
.0.0.1.0.0.0.0.0
.0.0.0.0.0.1.0.0
.0.1.1.1.0.1.1.1
.0.1.1.0.0.1.1.1
.1.1.1.0.0.0.0.1

Crossrefs

Sequence in context: A153892 A338410 A038869 * A147465 A053591 A165333

Adjacent sequences: A147500 A147501 A147502 * A147504 A147505 A147506

Keyword

nonn

Author

R. H. Hardin

Status

approved