A146657 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-0100-1111 pattern in any orientation.

1, 1, 1, 1, 5, 13, 49, 241, 1117, 5505, 34113, 304743, 3090983, 40451327, 642013469, 12875896245

Offset

1,5

Links

Table of n, a(n) for n=1..16.

Example

Maximal 8 X 8 example
.0.0.0.0.1.1.1.1
.1.1.0.0.0.0.1.0
.0.1.0.0.0.0.1.1
.1.1.1.1.0.0.0.0
.0.0.0.0.1.1.1.1
.1.1.0.0.0.0.1.0
.0.1.0.0.0.0.1.1
.1.1.1.1.0.0.0.0

Crossrefs

Sequence in context: A149536 A149537 A146689 * A243304 A238508 A151274

Adjacent sequences: A146654 A146655 A146656 * A146658 A146659 A146660

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved