A146694 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 9, 19, 37, 103, 317, 831, 2581, 12105, 62053, 307133, 1586103, 9856867, 66841097, 477861431

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.0.1.1.1.0.0.0.0
.1.0.0.1.1.0.0.0
.1.0.0.1.1.0.0.0
.1.1.1.0.0.1.1.0
.0.1.1.0.0.1.1.1
.0.0.0.1.1.0.0.1
.0.0.0.1.1.0.0.1
.0.0.0.0.1.1.1.0

Crossrefs

Sequence in context: A293058 A294367 A339495 * A146050 A147500 A300445

Adjacent sequences: A146691 A146692 A146693 * A146695 A146696 A146697

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved