A146840 Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 1001-1111-1000 pattern in any orientation.

1, 1, 1, 1, 1, 1, 17, 21, 525, 997, 11539, 28687, 537003

Offset

1,7

Links

Table of n, a(n) for n=1..13.

Example

Maximal 8 X 8 example
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.0.1.1.0.0.1.1.0
.0.1.0.0.0.0.1.0
.0.1.0.0.0.0.1.0
.1.1.1.0.0.1.1.1

Crossrefs

Sequence in context: A125613 A147052 A147132 * A146587 A147256 A147163

Adjacent sequences: A146837 A146838 A146839 * A146841 A146842 A146843

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved