A146688 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-1000-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 15, 35, 63, 133, 361, 1225, 3603, 14173, 68577, 327107, 1804859, 9535581, 56798795, 377223653

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.1.1.0.0.0.1.1.1
.1.0.0.0.0.1.0.1
.1.1.1.1.0.1.0.0
.0.0.0.0.0.1.0.0
.0.0.1.0.0.0.0.0
.0.0.1.0.1.1.1.1
.1.0.1.0.0.0.0.1
.1.1.1.0.0.0.1.1

Crossrefs

Sequence in context: A212331 A067930 A257836 * A146656 A229108 A160497

Adjacent sequences: A146685 A146686 A146687 * A146689 A146690 A146691

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved