A146245 Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 110-111-010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 3, 5, 5, 11, 11, 29, 29, 171, 171, 783, 783, 4399, 4399, 33371, 33371, 348951, 348951, 4490023, 4490023, 67743969, 67743969, 1262306965, 1262306965

Offset

1,7

Links

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

Example

Maximal 8 X 8 example
.1.1.0.0.0.0.1.1
.1.1.1.0.0.1.1.1
.0.1.0.0.0.0.1.0
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.0.1.0.0.0.0.1.0
.1.1.1.0.0.1.1.1
.1.1.0.0.0.0.1.1

Crossrefs

Sequence in context: A077953 A077980 A286759 * A245144 A279021 A339555

Adjacent sequences: A146242 A146243 A146244 * A146246 A146247 A146248

Keyword

nonn

Author

R. H. Hardin

Status

approved