A146702 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1111-0010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 9, 19, 33, 65, 197, 769, 3257, 13441, 53529, 253559, 1417627, 9502081, 68675873, 543081895, 4543747499

Offset

1,8

Links

Table of n, a(n) for n=1..23.

Example

Maximal 8 X 8 example
.0.0.0.0.1.1.0.0
.0.0.1.1.1.1.0.0
.0.1.0.1.0.0.1.1
.0.1.1.0.0.0.1.1
.1.1.0.0.0.1.1.0
.1.1.0.0.1.0.1.0
.0.0.1.1.1.1.0.0
.0.0.1.1.0.0.0.0

Crossrefs

Sequence in context: A146630 A146710 A146803 * A146734 A146614 A146670

Adjacent sequences: A146699 A146700 A146701 * A146703 A146704 A146705

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved