A146727 Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 1101-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 13, 13, 35, 35, 157, 157, 741, 741, 4435, 4435, 44453, 44453

Offset

1,11

Links

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

Example

Maximal 11 X 11 example
.0.0.0.1.1.0.1.1.0.0.0
.0.0.0.1.0.0.0.1.0.0.0
.0.0.0.1.1.0.1.1.0.0.0
.1.1.1.0.1.0.1.0.1.1.1
.1.0.1.1.0.0.0.1.1.0.1
.0.0.0.0.0.0.0.0.0.0.0
.1.0.1.1.0.0.0.1.1.0.1
.1.1.1.0.1.0.1.0.1.1.1
.0.0.0.1.1.0.1.1.0.0.0
.0.0.0.1.0.0.0.1.0.0.0
.0.0.0.1.1.0.1.1.0.0.0

Crossrefs

Sequence in context: A147136 A146844 A146193 * A146426 A146051 A146229

Adjacent sequences: A146724 A146725 A146726 * A146728 A146729 A146730

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved