A146938 Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 1111-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 2, 1, 4, 1, 6, 3, 13, 7, 38, 14, 126, 39, 447, 110, 1805, 377, 8300, 1728, 44775, 8445, 290627, 46261, 2170182

Offset

1,8

Links

Table of n, a(n) for n=1..30.

Example

Maximal 8 X 8 example
.0.0.1.1.1.1.0.0
.0.0.1.1.1.1.0.0
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.0.0.1.1.1.1.0.0
.0.0.1.1.1.1.0.0

Crossrefs

Sequence in context: A118275 A328612 A243824 * A147418 A146386 A305098

Adjacent sequences: A146935 A146936 A146937 * A146939 A146940 A146941

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved