A146590 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0110-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 5, 13, 25, 41, 73, 405, 2087, 9095, 31781, 109905, 706437, 6193961, 52066515, 395176419, 2801856537, 27230658787

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.0.0.0.0.1.0.0.0
.0.0.1.1.1.1.0.0
.0.1.0.1.1.0.1.0
.0.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.0
.0.1.0.1.1.0.1.0
.0.0.1.1.1.1.0.0
.0.0.0.1.0.0.0.0

Crossrefs

Sequence in context: A301671 A373059 A268525 * A098483 A147205 A146875

Adjacent sequences: A146587 A146588 A146589 * A146591 A146592 A146593

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved