A146129 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 3X2 zee 1,1 1,2 1,3 2,3 2,4 in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 29, 29, 249, 249, 3031, 3031, 82773, 82773, 3652185, 3652185, 277821789, 277821789, 35279858253, 35279858253, 7589314375275, 7589314375275

Offset

1,9

Links

Table of n, a(n) for n=1..24.

Example

Maximal 9 X 9 example
.0.1.0.1.0.1.0.1.0
.1.1.0.1.0.1.0.1.1
.1.0.1.1.0.1.1.0.1
.1.0.1.0.0.0.1.0.1
.0.0.0.0.0.0.0.0.0
.1.0.1.0.0.0.1.0.1
.1.0.1.1.0.1.1.0.1
.1.1.0.1.0.1.0.1.1
.0.1.0.1.0.1.0.1.0

Crossrefs

Sequence in context: A022363 A146226 A146423 * A146040 A146017 A210267

Adjacent sequences: A146126 A146127 A146128 * A146130 A146131 A146132

Keyword

nonn

Author

R. H. Hardin, Oct 27 2008

Status

approved