A146672 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-0111-0110 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 19, 43, 71, 159, 607, 2057, 8951, 43111, 227107, 1266527, 7483327, 50232185, 389882233, 3353662007

Offset

1,7

Links

Table of n, a(n) for n=1..21.

Example

Maximal 8 X 8 example
.0.0.0.0.0.1.1.0
.1.0.0.1.1.1.0.0
.1.1.1.0.1.1.0.0
.0.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.0
.0.0.1.1.0.1.1.1
.0.0.1.1.1.0.0.1
.0.1.1.0.0.0.0.0

Crossrefs

Sequence in context: A336792 A341087 A031393 * A146704 A103145 A100694

Adjacent sequences: A146669 A146670 A146671 * A146673 A146674 A146675

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved