A146273 Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 110-111-111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 37, 73, 449, 747, 5801, 13609, 176107, 460513, 50638553, 175114985, 12101446061, 47558080771, 3621711702133, 17293036158759, 2644218203849621, 14780059508466803, 7478633672499919605, 51302046629377975419

Offset

1,7

Links

Table of n, a(n) for n=1..24.

Example

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

Crossrefs

Sequence in context: A128388 A137833 A083748 * A146241 A217386 A083990

Adjacent sequences: A146270 A146271 A146272 * A146274 A146275 A146276

Keyword

nonn

Author

R. H. Hardin

Status

approved