A146604 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1111-0001 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 9, 9, 29, 29, 137, 137, 1079, 1079, 13093, 13093, 250867, 250867, 6233403, 6233403, 218750525, 218750525, 11495073517, 11495073517, 872282781415

Offset

1,9

Links

Table of n, a(n) for n=1..27.

Example

Maximal 9 X 9 example
.0.0.0.0.0.0.0.0.0
.1.0.0.0.0.0.0.0.1
.1.1.1.1.0.1.1.1.1
.0.0.0.1.0.1.0.0.0
.0.0.0.0.0.0.0.0.0
.0.0.0.1.0.1.0.0.0
.1.1.1.1.0.1.1.1.1
.1.0.0.0.0.0.0.0.1
.0.0.0.0.0.0.0.0.0

Crossrefs

Sequence in context: A076089 A046000 A147378 * A294691 A356839 A147172

Adjacent sequences: A146601 A146602 A146603 * A146605 A146606 A146607

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved