A147420 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1001-1111-0110 pattern in any orientation.

1, 1, 1, 1, 1, 9, 23, 64, 295, 1072, 4637, 27060, 195073, 1617157, 15822995, 190207942, 2553434864, 40752029560

Offset

1,6

Links

Table of n, a(n) for n=1..18.

Example

Maximal 8 X 8 example
.0.1.1.0.0.0.0.0
.1.1.1.1.0.1.1.0
.1.0.0.1.0.0.1.1
.0.1.1.0.0.0.1.1
.1.1.0.0.0.1.1.0
.1.1.0.0.1.0.0.1
.0.1.1.0.1.1.1.1
.0.0.0.0.0.1.1.0

Crossrefs

Sequence in context: A183338 A212676 A211478 * A259170 A057453 A282761

Adjacent sequences: A147417 A147418 A147419 * A147421 A147422 A147423

Keyword

nonn

Author

R. H. Hardin

Status

approved