A146837 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1001-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 7, 15, 37, 79, 151, 497, 1751, 6209, 28231, 127833, 673629, 3604831, 23345419, 158561859, 1232306475

Offset

1,7

Links

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

Example

Maximal 8 X 8 example
.0.0.1.0.0.1.0.0
.0.0.1.1.1.1.0.0
.1.1.0.0.1.0.1.1
.0.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.0
.1.1.0.1.0.0.1.1
.0.0.1.1.1.1.0.0
.0.0.1.0.0.1.0.0

Crossrefs

Sequence in context: A063592 A159792 A247606 * A146044 A048694 A041094

Adjacent sequences: A146834 A146835 A146836 * A146838 A146839 A146840

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved