A146925 Number of n X n binary arrays with all ones connected only in a 1001-1111-1001 pattern in any orientation.

1, 1, 1, 5, 13, 37, 117, 629, 5685, 56354, 602084, 7772959, 142197171, 3619248864, 116780772318, 4548516587793, 219091485187390

Offset

1,4

Links

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

Example

Maximal 8 X 8 example
.1.1.1.0.1.0.0.1
.0.1.0.0.1.1.1.1
.0.1.0.0.1.0.0.1
.1.1.1.0.0.0.0.0
.0.0.0.0.0.1.1.1
.1.0.0.1.0.0.1.0
.1.1.1.1.0.0.1.0
.1.0.0.1.0.1.1.1

Crossrefs

Sequence in context: A071100 A199108 A125734 * A146452 A146062 A201612

Adjacent sequences: A146922 A146923 A146924 * A146926 A146927 A146928

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved