A146790 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0100-1100-1111 pattern in any orientation.

1, 1, 1, 1, 5, 17, 67, 311, 1473, 7613, 68761, 661093, 8801627, 124939017, 2484498069, 53077957657

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
.1.0.0.0.1.1.0.0
.1.0.0.0.0.1.0.0
.1.1.1.0.0.0.1.1
.1.1.0.0.0.1.1.1
.0.0.1.0.0.0.0.1
.0.0.1.1.0.0.0.1
.1.1.1.1.0.0.0.0

Crossrefs

Sequence in context: A149694 A149695 A162270 * A149696 A096980 A339684

Adjacent sequences: A146787 A146788 A146789 * A146791 A146792 A146793

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved