A146835 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1001-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 5, 15, 25, 43, 113, 451, 1305, 6863, 22081, 100557, 420517, 2802713, 14484461, 126443483

Offset

1,8

Links

Table of n, a(n) for n=1..22.

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
.0.1.0.0.0.1.1.0
.0.1.1.0.0.0.1.0
.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: A053928 A146779 A146859 * A146795 A166479 A108814

Adjacent sequences: A146832 A146833 A146834 * A146836 A146837 A146838

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved