A147124 Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 1000-1000-1111-1000 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 183, 351, 3263, 7493, 94421, 245945, 5221197, 15740513, 1251933355, 4637231205, 678331261037, 3060437240807, 522754227927889

Offset

1,9

Links

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

Example

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

Crossrefs

Sequence in context: A305349 A030465 A147270 * A261110 A260172 A252070

Adjacent sequences: A147121 A147122 A147123 * A147125 A147126 A147127

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved