A147153 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1100-0111-0010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 5, 29, 53, 103, 395, 1381, 4229, 19741, 89165, 570891, 3054965, 21029525, 147769545, 1255506947

Offset

1,8

Links

Table of n, a(n) for n=1..21.

Example

Maximal 8 X 8 example
.0.0.0.1.1.0.0.0
.0.0.1.0.1.1.0.0
.0.1.1.1.0.1.1.0
.1.1.0.0.0.1.0.1
.1.0.1.0.0.0.1.1
.0.1.1.0.1.1.1.0
.0.0.1.1.0.1.0.0
.0.0.0.1.1.0.0.0

Crossrefs

Sequence in context: A224499 A107003 A141374 * A300777 A177831 A115706

Adjacent sequences: A147150 A147151 A147152 * A147154 A147155 A147156

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved