A147160 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1100-0111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 9, 25, 53, 97, 275, 939, 2977, 11455, 54387, 273381, 1565737, 8740687, 56416565, 398132663

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.1.0.0.0.0.0.1.1
.1.1.0.0.1.1.1.0
.0.1.1.1.0.1.0.0
.0.1.0.0.0.1.0.0
.0.0.1.0.0.0.1.0
.0.0.1.0.1.1.1.0
.0.1.1.1.0.0.1.1
.1.1.0.0.0.0.0.1

Crossrefs

Sequence in context: A371085 A362971 A348232 * A336669 A239745 A269440

Adjacent sequences: A147157 A147158 A147159 * A147161 A147162 A147163

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved