A146263 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 110-111-101 pattern in any orientation.

1, 1, 1, 1, 5, 33, 133, 785, 3005, 17673, 190185, 2271593, 28110409, 628123625, 14202428649, 408602739063, 12463530182045

Offset

1,5

Links

Table of n, a(n) for n=1..17.

Example

Maximal 8 X 8 example
.1.0.1.0.0.0.0.0
.1.1.1.0.0.1.1.0
.1.1.0.0.0.0.1.1
.0.0.0.0.0.1.1.1
.1.1.1.0.0.0.0.0
.1.1.0.0.0.0.1.1
.0.1.1.0.0.1.1.1
.0.0.0.0.0.1.0.1

Crossrefs

Sequence in context: A050830 A211059 A292000 * A359703 A255943 A270222

Adjacent sequences: A146260 A146261 A146262 * A146264 A146265 A146266

Keyword

nonn

Author

R. H. Hardin

Status

approved