A147373 Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 0111-1100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 4, 1, 8, 3, 22, 9, 79, 19, 256, 42, 946, 149, 4545, 642, 27699, 3217

Offset

1,9

Links

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

Example

Maximal 9 X 9 example
.0.0.0.1.0.1.0.0.0
.0.0.0.1.0.1.0.0.0
.0.0.0.1.1.1.0.0.0
.1.1.1.0.1.0.1.1.1
.0.0.1.1.0.1.1.0.0
.1.1.1.0.1.0.1.1.1
.0.0.0.1.1.1.0.0.0
.0.0.0.1.0.1.0.0.0
.0.0.0.1.0.1.0.0.0

Crossrefs

Sequence in context: A200583 A366842 A115120 * A147441 A146269 A146679

Adjacent sequences: A147370 A147371 A147372 * A147374 A147375 A147376

Keyword

nonn

Author

R. H. Hardin

Status

approved