A146248 Number of n X n binary arrays with all ones connected only in a 110-111-011 pattern in any orientation.

1, 1, 3, 9, 21, 85, 755, 7735, 87315, 1464567, 39342833, 1394115639, 64760833633, 4237428548705, 396489545524701, 50966003405928397, 8978681383047868049, 2201121987520740127861

Offset

1,3

Links

Table of n, a(n) for n=1..18.

Example

Maximal 8 X 8 example
.0.1.1.0.0.1.1.0
.1.1.1.0.0.1.1.1
.1.1.0.0.0.0.1.1
.0.0.0.0.1.1.0.0
.0.0.0.1.1.1.0.0
.1.1.0.1.1.0.1.1
.1.1.1.0.0.1.1.1
.0.1.1.0.0.1.1.0

Crossrefs

Sequence in context: A053499 A218003 A146909 * A074000 A067645 A101474

Adjacent sequences: A146245 A146246 A146247 * A146249 A146250 A146251

Keyword

nonn

Author

R. H. Hardin

Status

approved