A146278 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 110-111-111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 5, 17, 29, 45, 101, 297, 821, 2819, 10635, 50419, 205159, 928911, 4321051, 24702095, 144781137, 1031901327, 7307383577, 64959695293, 541722263927, 5441453632793

Offset

1,7

Links

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

Example

Maximal 8 X 8 example
.0.0.0.0.1.1.1.0
.1.1.0.0.1.1.1.0
.1.1.1.0.1.1.0.0
.1.1.1.0.0.0.0.0
.0.0.0.0.0.1.1.1
.0.0.1.1.0.1.1.1
.0.1.1.1.0.0.1.1
.0.1.1.1.0.0.0.0

Crossrefs

Sequence in context: A242025 A027703 A075695 * A034937 A024351 A246325

Adjacent sequences: A146275 A146276 A146277 * A146279 A146280 A146281

Keyword

nonn

Author

R. H. Hardin

Status

approved