A146285 Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 111-110-111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 5, 1, 11, 5, 29, 13, 127, 25, 445, 59, 1927, 333, 10103, 1935, 78527, 9121

Offset

1,9

Links

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

Example

Maximal 9 X 9 example
.0.0.0.1.1.1.0.0.0
.0.0.0.1.1.1.0.0.0
.0.0.0.1.0.1.0.0.0
.1.1.1.0.0.0.1.1.1
.1.1.0.0.0.0.0.1.1
.1.1.1.0.0.0.1.1.1
.0.0.0.1.0.1.0.0.0
.0.0.0.1.1.1.0.0.0
.0.0.0.1.1.1.0.0.0

Crossrefs

Sequence in context: A133730 A330773 A112031 * A146059 A046531 A289310

Adjacent sequences: A146282 A146283 A146284 * A146286 A146287 A146288

Keyword

nonn

Author

R. H. Hardin

Status

approved